. >> what do you think r.b.nds for? >> we don't know what r.r. stands for. police will take we which he is how we come together. some of the buildings are back behind me. we are move towards pushing for more respect for one oochanothe. it is not going to tear us further apart. it will bring us closer together. >> does it make it more difficult because texas is an open carry state? one would argue thursday night at the protest it was a very confusing time to understand who is the shooter was when there were a number of people carrying weapo weapons. >> reporter: well, i think the main confusion for us as far as the danger was the fact that he was using shoot and move tactics. the fact that there were marchers with wrong guns in the procession, it wasn't --. it could have been used for tls if he was on top of us. he was shooting us in the back. >> and you mentioned how the done launching eerm why do you feel that will happen. it is a are tranl we showed it when we indicted the others ear we see we can show more re

that is one of the things that the investigators are trying to unravel and the initials "r.b." according to micah johnson wrote with his own blood in two locations in the community college building. john. >>> thank you, ed. the shooter's parents are speaking out saying his time in the army changed him turning him from an idealist to a police officer to a hermit. the gunman's father said he was stunned by his son's actions. >> i don't know what to say to anybody to make anything better. i didn't see it coming. >> overnight, new protests across the country against what demonstrators called police brutality. in atlanta, police arrest 16 people after hundreds took to the streets protesting the killing of two black men, one in louisiana and one in minnesota, by police. the protesters marched to the georgia governor's mansion. cnn's polo sandoval has more from the scene. >> reporter: the city of atlanta, one of several across the country, erupting with protests for the fifth night in a row. we marched with demonstrators part of the black lives matter movement making their way to the

he wrote letters "r.b."figure out, looking through things in his home what those initials mean. >> now, part of the selection of the things in his home the chief was talking about there. the police are going to look at the laptop where they found evidence of radicalization through several hate groups. they'll look at his contacts to see if r.b. are initials or an acronym for some other group. aside from the investigation, the healing process has begun. there will be a vigil in front of city hall tonight. and of course the big citywide memorial tomorrow. president obama, vice president biden will be here as well. dallas residents former president george w. bush and former first lady laura bush will be there. the president and the former president will both speak. ana. >> thank you from dallas, victor blackwell. >>> some new details we're learning. tom fuentes, cnn senior law enforcement analyst, and ryan zalens, former nypd hostage negotiationer. we heard from dallas there is evidence this killer was planning

during the investigation they might find out what r.b. means. >> and you told me how this killer was planning something else and he saw the protest as an opportune time to have a lot of police officers exposed in one place. how is this guy able to seemingly unnotice move through the crowds? >> i'm saying to myself, the only way he could have done that is if he had people walking with him to cover him. i find it hard to believe she walking through the crowd with a lot of weapons. it tells me the weapons could have been planted in the places he was going to conduct the attack. the key here is if you see something say something. a lot of people saw a lot and said nothing. >> and to that point, i think many people in communities are hesitant to say something for fear of who may be in their background or fear of retaliation from the suspect in this case, the killer in this case that had not died. >> they could remain anonymous. after one of the fox interviews i had i received an e-mail with evidence and information. because of what fox is doin

of the initials r.b. >> reporter: tense negotiations lasting two hours. authorities saying johnson was laughing and singing. >> there is indications of ranting in his writings and some of the things that he said to hostage negotiators. >> reporter: knowing officers were down, the police chief finally deciding to send in a robot carrying a pound of plastic explosives. >> i'd do it again to save our officers' lives. >> reporter: tonight, the gunman's family struggling, telling the website the blaze -- >> i didn't see it coming. i love my son with all my heart. i hate what he did. >> reporter: dallas tonight on edge, presided over by a police chief possibly in the cross-hairs. yesterday, i noticed that your bodyguard was guarding you very, very carefully. there have been threats against the department. have you received personal death threats against you? >> yes, me and my family have received death threats almost immediately after the shooting. >> reporter: but still sending this message tonight to his community. >> become apart of the solution. serve your

the chief said johnson wrote on the ground and wall with his own blood "r.b."estigators are trying to figure out the reference. there were other writing that he left in his own blood as well. then, the chief says that johnson requested that he would only speak with a black negotiator at the scene. all of this while micah johnson continued to fire rounds of shots at the officers in the scene. the police chief describes micah johnson under control and delusional. asking how many officers he had been able to kill. the police chief says there is clear evidence that micah johnson was mounting an arsenal and had a bigger planned attack, but switched and decided to make his attack last thursday night. >> it appears our search of the suspect's home in mesquite leads us to believe based on evidence of bomb making materials and a journal that the suspect had been practicing explosive detonations and the materials were such that it was large enough to have devastating effects throughout our city and our north texas area. we're convinced this suspect had other plans and th

is there any more insight into those initials he wrote in blood, r.b.? >> reporter: no, in fact, investigators talked about that again today. they continued to try to figure out what that means. according to the police chief here in dallas in his own blood, micah johnson wrote the initials, r.b., in two different locations inside the community college building where he was shot -- where he was killed on friday morning, essentially. they're still trying to figure out what that could mean. >> ed lavendera. ed, thank you very much. i want to bring in martin now at dallas city hall. so, martin, to you now, you are at the candlelight vigil in dallas. president barack obama arriving tomorrow and the funerals are being set. what is the city like this evening? >> reporter: you know, it's really hard to put it into words, don. if you could find one, it would be heartbreak for this evening. a very large crowd showed up for this candlelight vigil. more than that. opportunities for individuals, police partners, who spoke about their loss, spoke about the partner tha

the initials "r.b."ten in his own blood on the walls of the parking garage where he was cornered. it's one of many questions facing investigators that are trying to figure out why one man took so many lives. >>> new details on the southern california fire that burned to the edges of homes north of los angeles. the fire is almost 50% contained. it's no longer threatening these houses. evacuations have been lifted by 2,000 people were forced out yesterday. no word on what caused the fire. >>> the cause of a small brush fire in redwood city is still being investigatored tonight. it started at 10:00 this morning. smoke billowed threw the parking lot of this shopping center. investigators say the flames burned a palm tree and brush near a homeless encampment. >>> an air quality warning in san jose. fogging for mosquitoes will happen on wednesday night and thursday morning. mosquitoes and birds with west nile virus were found in san jose. if you live in those areas, keep your pets indoors that night and close

working also with our law enforcement partners in the area to determine the meaning of the initials r.b. that were adescribed on the walls there in two locations inside. >> there is much more developing at this hour. fox news rick leventhal is in dallas. rick, what's the latest? >> greta, we're outside city hall tonight where the city is preparing for a caneld light vigil. the dallas strong cagetedz light vigil begin two hours from now. chief darryl brown will be here with city leaders and other officers who will speak on behalf of those five officers killed last thursday night. chief brown revealed a lot more information about what investigators have learned since those thursday night shootings but also about how much more work is left to be done. you heard him talking about all that video they have to go through to create a video time lynn of the events last thursday night. also reviewing 300 interviews that they did with witnesses to determine who, if any, of them need to be interviewed. they also revealed some at the scene never gave statements. they are also ck track to do down to

do major damage throughout north texas and left a message behind high pressure he left the message r.b. in blood in the building where he died. after protests there ended and itsed injuries and arrested. >> president obama is headed to dallas now to attend a memorial service there. he will arrive back in the u.s. chedult and then will travel to dallas. oasident obama will then be speaking at an interfaith memorial service, and that is scheduled for tuesday. >>> friends and family of a shllejo woman are holding out aturdahat she is still alive. on july 1st, she called police, told police she was kidnapped and being held for ransom. ftvestigators made four arrests in the case. one of the suspects lived in her building several years ago. al> and a woman who died in an accident in el dorado river yesterday. this is about 150 miles east of san francisco. police say they received a call around 4:00 in the afternoon. mau was with a rafting group andhehe fell overboard and into the water. >> two wrongs don't make a right. that is the message that the police want you to know after a driver and

they are trying to figure out what r.b. stand for. >> a person who was well-prepared, thinking ahead, who was talking about shoot and move tactics, that's important because we had on the scene information from witnesses about shooting from different places. detectives found a personal arsenal at the home johnson shared with his mother. neighbors said johnson practiced combat drills in his backyard. >> a unity service in montgomery county had an upbeat tune to it yesterday. the police department was invited to the lamont ame m church. they are hoping services like this will help ease tensions between the police and the community. >> it is 6:06. >>> a philadelphia firt tefight is in the hospital after being hurt in this wynnefield neighborhood. crews were called to the area around 1:00 a.m. everybody got out safely. the firefighter is expected to be all right. >>> two brothers that admitted their roles in a shooting outside a funeral in trenton are headed to prison. samuel vinson received a seven-year sentence, his mother sam

according to the police chief in dallas, in micah's own blood he wrote those initials, r.b. in two different locations, in the community college building where he was killed essentially, so ne they're still trying to figure out what that could mean. >> martin, to you now, you are at the candlelight vigil in dallas. president obama arriving tomorrow. and the funerals are being set. what is the city like this evening? >> reporter: you know, it's really hard to put it into words. i think if you tried to find one, it would be heartbreak. people showed up for the candlelight vigil, but it was an opportunity for each of the fallen officers, mainly co-workers, to speak about those that they loest. talking about the events of the evening and how they inspired them throughout their lives. they broke up. many in the crowdmany in the cr them broke down. it is a very painful time. the shock now beginning to wear off, but now we face a week of funerals. and it is going to be incredibly difficult, the weight of laugs on this city is extreme lly hea. the nation has to come together. and a

. >> still a mystery why johnson scrawled the letters r.b. on the wall in his own blood before he died. >> do you know why this man was stockpiling ammunitions and guns inside his home? >> that's my question. >> reporter: investigators have questioned johnson's mother, in her first interview with "the blaze" says she watched her son turn from a fun loving person into an activist. >> his father is grief stricken as he tries to understand what drove his son to violence. >> i didn't see it coming. >> reporter: how would you describe micah? >> he was a good son. >> he was a good son. >> i loved my son with all my heart, but i hate what he did. >> reporter: on social media, johnson showed an interest in the black power movement, but police have not confirmed any formal ties to any organization. tonight dallas is still on edge. >> to be quite honest, i'm running on fumes. >> reporter: a candid chief brown calling for changes in the demands on overwhelmed police officers. >> we're asking cops to do too much for this country. >> reporter: and a docto

working also with our law enforcement partners in the area to determine the meaning of the initials "r.bwere scribed on the walls there in two locations inside el centro. all of the police vehicles that were processed by the fbi at the scene have been taken to the naval air station here to ensure that officers personal property is returned to the families when appropriate. can i also give -- before i take questions, just an overview of the work that dallas police officers have done here in dallas to protect citizens. 2015, just last year, was our unprecedented 12th consecutive year of crime reduction. for a total of 53% reduction in crime. more than any major city in this country during that period. and more than at any other time in our history here in dallas. we have our records back to 1930 to today. in 2015, we had our fourth lowest murder rate since 1930. that followed 2014 was our second lowest murder rate since 1930, in over 86 years. 2011 was our fifth lowest murder rate in our city's history. 2013 was our sixth lowest murder rate. and 2010 was our tenth lowest murder rate. and t

>> we are trying to decipher that, but he wrote the letters r.b. >> r.b. >> yes. we're trying to figure out through looking at things in his home what those initials mean. but we haven't determined that yet. >> after the shooting, you suggested that the gunman had to have had some knowledge of the parade route. you said, how would you know to post up there? and you also said you have yet to determine whether or not there was some sort of complicity with the planning of this. have you learned anything more about that? >> yes. we had information prior to the rally that the rally would only be a static event at the gardens. after the rally, people would leave peacefully. we had no indication that anyone was planning any type of violence to our people or damage to our properties. so we really did our security planning around the things that we learned from the preplanning meetings that the protesters had. spontaneously they began to march. and there was no route determined before this spontaneous march began, and they just began walking. what we know now is that this

. >> reporter: in an interview david brown revealed the chilling mystery, he wrote r.b. where they cornered him. he would only speak to black officers. chief brown said he had no choice but to use a robot delivered bomb to kill the gunman. >> we believe we saved lives by making this decision. >> reporter: they are dilging through his rambling writings for more clues. >> he was thinking ahead. he was talking about shoot-and-move tactics. we had information about shooting from different places. >> reporter: detectives found a personal arsenal and neighbors say he practiced combat trails in his backyard. a threat against law enforcement, a quick response, no suspect found. >> thank you, dave. >>> president obama cut his european travel short. vice president joe biden and laura bush will also be in attendance. edward joins us live with more. what can we expect from this visit? >> good morning. we can expect healing to start to happen. the president is waking up in the white house this morning. he will get a briefing on the dallas information that killed five officers. presid

and is it a possibility that he the letters r.b. could have been part of an acronym could have been used? >> we don't have that information to confirm. either of those. we are following any and all leads. i am a little bit old-school cop. until you show me we've exhausted every lead, i'm not going to be convinced that we know everything. about what happened, associations, others that might be complicit. so i'm going to -- we're going to turn over every rock. we're going to follow every lead until this is exhausted, until i'm satisfied that this was the lone person. and i may be overly concerned about this. but i'm highly protective of cops. and i'm going to make sure there is nobody else out there that had something else to do with this. >> how is it possible that -- the family being young, is stock piling weapons in his home. >> you sound like a cop, brother. that's my question. emmanuel? >> thank you. as far as the investigation, knowing what you know now, is there anything that could have been done to prevent this attack? and on

they revealed he scrawled the letters r.b. in his own blood on the walls of the parking garage. investigators are trying to figure out what that stands for. >> this was a person well prepared, thinking ahead, talking about shoot and move tactics. that's important. we had on-the-scene information from witnesses about shooting from difference places. >> detectives found a personal arsenal at the home johnson shared with his mother. neighbors say he practiced combat drills in his backyard. >> two children are in the hospital after they were hit by a car while riding their bikes in montgomery county. sky 410 is ov m 10 is over the . they were riding bikes and the driver that hit them stayed on the scene. the boys are expected to recover. >>> seven minutes after 5:00, just over a half hour away from sunrise. a news view. some scattered clouds. clear skies overnight. it has cooled down this morning. a cool morning. we will see a sunny, warm afternoon. fortunately, the humidity stays low. a little bit of a northerly wind will be keeping the humidity low and making for a mainly clear an

. >> reporter: brown also mentioned the suspect wrote the letters r.b. in his own blood on the walls of the parking garage, where s.w.a.t. teams cornered him. meanwhile, over the weekend, protests erupted in states recently affected by police shootings. minnesota and louisiana. and cities protesting in solidarity from the east coast to the west coast. over the killings of african-american at the hands of police. and the president still facing tremendouses about the feeling among law enforcement that he sides more with activists than police. betty? >> all right, lawrence, thank you so much for that. >>> the family of one of the officers killed in the attack is speaking out for the first time. the mother and sister of officer patrick zamarripa, valerie and laura talked to msnbc's chris jansing about his love for family and how they learned of patrick's death. >> well, first of all, thank you for doing this. >> thank you. >> tell me about patrick. >> patrick was a fun-loving, crazy, wonderful human being. wonderful. everybody loved him. >> he was your middl

in the heart of dallas where his standoff ended just a few blocks behind me, they found the initials r.b. written in blood. police don't yet know what that means. and while investigators have still not ruled out whether others were involved, they were careful to note the sophistication of his tactical approach. unusual for most criminal suspects. >> -- such a spontaneous decision to march by the protesters, we had to leapfrog intersections to make sure they didn't get run over by vehicle. and we had to scramble to block intersections, which did expose our officers to this attack. and this suspect took advantage of that, and once he was in a high perch position, officers did not know where the shots of coming from and we are learning some of the positions of our deceased officers, and it was -- they were in a funnel, ended up being a fatal funnel there, and then the suspect continued to move and shoot from different angles. really diagonally, almost triangulating our officers with his rapid fire. >> they also confirmed he requested a black police negotiator as the night wore on. and the c

he wrote the letters r.b. on a wall before johnson died.ing johnson's home trying to figure out what those initials mean. they found a journal containing tacticing and a journal containing arsenal and lost by the rapid transit police. all served in the dallas police department. wounded in the ambush, he saw three members of his unit killed. >> being there and watching people that, you know, we see every day. people that we get to know their families. we get to know them personally, at a level that you can't even imagine. we ride around in the car eight, sometimes more hours, stinky, sweaty -- you know, everything. and then we go through things that most people don't see in they are entire life. you get really close to people. and these were my brothers, and i -- i hate to s was -- i -- frustrated, because i couldn't do more. >> saying officers zamarripa bought a homeless man food during a protest. that was just before zamarripa was gunned down. he said it represents the character of his colleagues who were killed. >> protest over police kil

police say micah johnson left this chilling clue, the letters r.b. scrawled twice on a wall in his own blood. could it lead to a motive. and inside this story. >>> a fox news scandal. was one of its anchors sexually harassed by roger ailes. >>> what are micah johnson's friends and family saying about him tonight? >> reporter: his parents gave an interview. and his father said they did not see them coming. they described him as a good son. and his mother went on to say that after i le-- he left the military he became very disillusioned. >> what have investigators found inside his home? >> reporter: investigators are still trying to sift through this mystery. they found bomb-hamaking materials. we heard from a federal law enforcement source that said it was about 3.5 pounds of explosive material. a law enforcement official tells me that that material was spread out throughout various rooms in the house, but what was the intent, what was it supposed to be used for, and that's what police don't know at this point. >> i now that chief of police brown held

writing r.b. and other messages on the wall in his -- his own blood before they killed him with a blast. the fbi supporting dallas police department with 150 agents and other specialists, including some 70 members of the evidence response team painstakingly photographing and recreating the scene which could take two more days. we also now heard from at least one of the survivors, 37-year-old was at the protest march thursday and was shot in the calf while shielding her boys from the bullets. >> said yes, sir, i am hitting -- hit in my leg. that officer jumped on top of me, covered me. my son. there was another one at our feet. another one over our head. several of them lying against the wall over there and they stayed there with us. i saw another officer -- i saw another officer get shot in front of me. >> reporter: a lot of tears at the news conference today from taylor and her son. she said she hopes the community can come together, we are seeing that community come together outside police headq

and he crawled messages from his own blood in the parking lot he was hiding out including r.b. the chief say they're trying to decipher along with the other things he crawled in his own blood. >> one of the victims speak out at the hospital, an emotional poignant heartfelt plea. >> reporter: 37-year-old shetamia taylor said she went to that protest with her four sons because she was upset about the shootings of two black men by white police officers and then she was shot in the calf, and it shattered her tibia, and that happened after she threw herself on top of her boys to shield from from the gunfire and says she is thankful for the dallas police department. >> i'm so thankful for the dallas police department and atf, i don't know who was down there, i'm thankful to all of them. they had no regard for their own life and they stayed with us and stayed with myst son and i'm so thankful for that. >> reporter: taylor and her sons shed tears at that emotional news conference and said she wants to see this community unified. we are seeing that unity in full force at this memorial s

the initials r.b., a message police are still trying to decipher. this as we're learning more about the five officers whose lives were cut short protecting a peaceful protest. >> no, not my baby. not my patrick. >> reporter: 32-year-old patrick zamarripa, the engaged father of two, was a navy veteran and just weeks away from his 33rd birthday. his family says his dream was to become a police officer. >> my brother loved his country and his community. i just can't wrap my mind around it. it's just so unreal. >> since day one, since he was born, he was a hero. he was my little hero. he's a big hero now. >> reporter: those who did survive the ambush are grateful to be alive. the dallas mother protected her four sons when shots rang out. she was hit in the leg as officers were shot in front of her. taylor thanking police for their heroism in the hail of bullets. >> it hurt. of course i'm thankful that my babies are okay, but somebody's dad, husband isn't. >> reporter: we've learned that president obama and vice president joe biden will be arriving tomor

really astounding and one of the big things is michael johnson wrote in his own blood the initials r.b. in the parking garage. investigates are trying to figure this pertinent to the shooting. police chief earlier today described michael johnson as delusional. the entire time he was involved in the standoff he was taunting the police officers. and singing and laughing at them. and at a point where they didn't think the negotiations could go any further that is when they sent in the robot with the explosive device. and he really thought that michael johnson wanted to kill other people. the big question is was there anybody else involved? let's listen to what the police chief had to say. >> we still haven't ruled out, jay, whether or not others were complicit. and just the way we do things. we want to make sure we follow every lead and make sure we don't miss any pieces of evidence that might lead to other things that we don't know yet. >> and we are just two blocks from the shooting. but as we've talked about, most of downtown is completely closed off and that is because investigators a

we're also told that micah johnson, the gunman, was wounded and wrote the initials r.b.his own blood on the walls, but officials still aren't sure what that means. two college students stayed in that building overnight because they were too scared to leave. the chief also says, he confirms that johnson had a large stockpile of bomb-making materials in his home, the home that he shared with his mother, but they still don't know if he planted explosive devices anywhere or if he planned to. and, liz, the chief says he is determined to insure or to confirm that johnson was, in fact, the lone gunman and did not have any help. liz: thank you very much. rick, thank you. it's a tough story to cover, and we appreciate it. let us know if there are any new details. we'll interrupt the show if you get them. folks, if you're left wondering how police can remain safe when they're getting shot at by people who have these weapons, coming up who knows how many lives can be saved by this. robocops. one was deployed in dallas to stop the shooter. we've got the ceo of a robocop company. you

working also with our law enforcement partners in the area to determine the meaning of the initials r.b. that were scribed on the walls there in two locations, inside el central. >> the police chief also strongly defended how the police ended thursday's standoff with a bomb on a robot. >> we knew through negotiations, this was the suspect because he was asking us how many did he get. and he was telling us how many more he wanted to kill. this wasn't an ethical dilemma, for me. i'd do it again, keith. i'd do it again to save our officer's lives. >> president obama having cut short his trip to spain returning to d.c. late last night, will take part in the memorial along with former president bush tomorrow in dallas. >>> meanwhile, protests escalating across the country in response to the controversial police killings of two african american men early last week. in baton rouge, there were dozens of arrests as protesters clashed with police overnight. in in minnesota, more than 100 people were arrested, 21 police officers were injured over the weekend. our team has a all covered. nbc's jake

working also with our law enforcement partners in the area to determine the meaning of the initials r.bhat were scribed on the walls there in two locations inside el central. >>> president obama arrived back at the white house late last night and heads to dallas tomorrow for an inner faith memorial service. joining me now is a cofounder and arguably the best-known face of the black lives matter movement. this is one of his first interviews since being arrested saturday for demonstrating in baton rouge and spent 16 hours in jail before being released yesterday. deray thank you for joining me, i appreciate it. >> it's good to be here. >> so first, i just want to start off, how are you doing today? how were you treated during those 16 hours? >> i'm good, i'm good. i'm tired. it was a long 16 hours in jail. and so many people who were in there with me and people who are still waiting to be released. remember, i nobody founded the movement, the movement was founded by the people in st. louis in 2014, i'm one of many who do the work. i feel okay, and you know, the arrest will not make any of

there has been a lot of speculation about what exactly was meant when he scrawled those two letters r.b. in his own blood on the walls as the police were negotiating with him. police chief said he wrote that in two locations, and they are not confirming exactly what this is yet. there had been speculation that perhaps they may have had something to do with an acronym used by a black power organization. so all that is still to be determined but again, the chief says this is all making a very large toll on the department. and today he talked about the larger issue of police officers in this country. here's what he had to say. >> we're asking cops to do too much in this country. we are. we're just asking us to do too much. every society failure, we put it off on the cops to solve. not enough mental health funding. let the cop handle it. not enough drug conviction funding. let's give it to the cops. here in dallas, we've got a loose dog problem. let's have the cops chase loose dogs. >> now the chief also said today that he had misspoken earlier by saying that the interaction between police,

and before the killer was blown up by a police robot, he apparently used blood to write the letters r.b. on the walls of the parking garage. it remains unclear what those letters stand for, megyn. >> trace, thank you. we wanted to speak with people who are at the heart of this issue, and in fact two of our panelists could not be here tonight because they were arrested this past weekend. black lives matter activist deray mckesson, who trace just told you about, was actually suppose to be here tonight, plus jay mel green had agreed to be here before police in chicago arrested him. his attorney is here to speak on his behalf. thank you all, panel, so much for being here. it's obviously a very difficult issue. i'll ask all of you, whoever wants to volunteer, why you think this time we haven't already gotten to a place of, all right, let's lower the temperatures. what we're seeing in the wake of last week is an escalation of sorts after what we saw in dallas and after what we saw in louisiana and minnesota. things seem to be getting worse and more inflamed. anyone want to take that? go ahead

the letters, r.b. scrawled twice on a wall in his own blood. what does it mean? and could it lead investigators to a motive? plus, inside this story. a fox news scandal. was one of his lead anchors s sexually harassed by the chief of the network, robert ailes? ed, i'm going to begin with you for the new details on this. what are micah johnson's friends and family saying about him tonight? >> reporter: well, you know, his parent s gave an interview to "the blaze" website and his father said he did not see this coming. they described him as a good son and his mother went on to say that after he had left the military, he'd become very disillusioned so those are some of the first words that are coming from his parents. >> what have investigators found inside of his home? >> reporter: well, you know, this is an interesting part where investigators are still kind of trying to sift through this mystery of, you know, they found bomb-making materials that they talked about for the laugh c last couple of days. a federal law enforcement source said it was about 3 1/2 pounds

r.b.?ah, our program, basically we use the creativity by using duct tape and spray paint to make awesome bikes. >> reporter: so they come and decorate their bikes, but this isn't just an after-school program type of thing, this is to keep kids if schools. what do you need to do to be part of the team? >> you have to have at least a 2.5 gpa, joy to have your own -- you have to decorate your own bike, and you have to volunteer at the shed. the address is 6833 international boulevard, and we're accepting all volunteers and donations, as well. >> reporter: so they come to a shop, and here is an example of what they maybe do with their bike? >> yeah, this is alumn null foil tank on a customized bike. we put the foil on, duct tape, spray paint. whatever you need to make a beautiful bike, you know, decorating. >> reporter: so you guys will be out here before the parade starts, but you'll be out here to the entire day, as well. so the kids can come by even after the parade, decorate their bike. thi

the chief says that johnson wrote on the ground or on the wall with his own blood the initials r.b. investigators are still trying to figure out what that is a reference to. they haven't figured that out yet. also some other writing left in his own blood as well. and then the police chief also says that johnson who requested that he would only speak with a black negotiator there at the scene. all of this while micah johnson continued to fire rounds of shots at the officers who were there inside the scene. the police chief describes micah johnson as someone who is very much under control yet delusional, at times singing and laughing at the officers, asking about how many of the officers he had been able to kill throughout all of that scene. the police chief also says there's clear evidence that micah johnson was mounting an arsenal and perhaps had a bigger planned attack. but for some reason switched and decided to make his attack last thursday night. those are some of the details revealed by the police chief in an extraordinary interview with cnn. >>> u.s. president barack obama wil

. >> reporter: the fbi is also investigating those cryptic letters, r.b., written by the gunman in twolaces, in his own blood during the standoff. the chief also mentioned that he and his family have received death threats following the attack. and that he is considering mandating counseling for his officers for those who need help don't have to ask for it. gayle. >> thank you very much, manuel. family members offered members of the fallen officers at an dallas city hall. the colleagues displayed portraits of the five officers who were killed. more than 1,000 people gathered in candlelight to mourn. omar villafranca was there. >> good morning. last night's ceremony was partly memorial and partly support. there were two main themes love and unity. >> we bowed our heads, we have it backed up. we're holding it high. >> reporter: more than 1,000 people gathered to pay respects to the five officers killed in dallas thursday night. officer brent thompson. >> a shining example of what it means to be a warrior. >> reporter: officer patricio zamarripa. >> it was easy to see the joy when he smil

working also with our law enforcement partners in the area to determine the meaning of the initials, "r.b." that were scribed on the walls there in two locations inside. >> as we mentioned, those mysterious initials you just heard the police chief referred to were scrawled in blood where the shooter had holed up before his death. also today, the dead shooter's father, mother, and stepmother are openly expressing their own shock and heartbreak and what they think may have caused him to snap. i'm joined now by cnn's victor blackwell, he has been covering this story for us from dallas. there he is. before we get to the parents, that interview, what else did the police chief reveal and what are you learning about the weaponry used in this ambush? >> reporter: let's start with the weaponry. we're learning from a law enforcement source who has knowledge about the investigation about, first, that semiautomatic rifle, the semiautomatic assault style rifle. a 545 caliber, which is a variation of the ak, that was the weapon that he used to injure so many people on thursday night. also, a glock 19,