the copier. >> lester holt joins us next. on this thursday night, the manhunt from d.c. now to new york, a huge break in the shocking family murder mystery has leftover pizza inside the home puts police hot on the trail of the suspected killer. a state of emergency declared amid a frantic race to clean up all the oil spilled off california. the officer gunned down the day before she was to bring her newborn home from the hospital. the family and the city left reeling from an awful tragedy. the world treasure now in the handsch isis. amid fears these ancient ruins could be destroyed. and risk factors, testing for your baby's health earlier than ever, but can those prenatal tests be trusted?

one couple warns of a tragic decision they nearly made. "nightly news" begins right now. >> announcer: from nbc news world headquarters in new york, "nbc nightly news," lester holt. good evening. there's been a big break in the family murder mystery in washington, d.c. that we have been telling you about the last several nights. tonight, police from washington to new york are on the trail of a 34-year-old man suspected of holding an affluent couple, their young son and housekeeper hostage before killing them leaving their bodies in the family's burning mansion. the break right out of a csi episode. a pizza crust and a dna match. how police did in a moment, but first, the suspect, a man with an apparent previous connection to his alleged victims. peter alexander is on the story. peter? >> reporter: lester, good evening. police say the suspect in these vicious murders is a former employee of savvas savopoulos' iron company. and tonight our

station wrc is reporting that one of the suspect's relatives was fired from that company. police say the suspect is armed and dangerous. his whereabouts unknown. a major break in a horrific crime. detectives matched dna from pizza crust found in the savopoulos family mansion to daron dylon wint now suspected in the brutal murders. tonight law enforcement sources tell nbc news the 34-year-old maryland man, wanted for first-degree murder, may be hiding in brooklyn, new york. after taking a bus to see his girlfriend who police have interviewed after leaving her apartment early this morning. >> it does not appear this was a random crime but there is a connection through the business of the savopoulos family. >> reporter: savvas savopoulos was ceo of american iron works where police say wint once worked. the murder suspect has a criminal record. in 2010, wint was arrested outside american iron works carrying a two-foot long machete. weapons charges were

dropped after he pleaded guilty to possessing an open container of alcohol. do you believe there were multiple suspects involved or that wint was acting alone? >> we have not ruled out there was others involved. i can't comment beyond that. >> reporter: the terrifying ordeal began last week, his wife, son and housekeeper all held captive inside. a clerk at this nearby's dominoes told nbc news that they delivered pizza to the mansion that night unaware there were four hostages there bound and threatened. the next morning, his assistant delivered a package with $30,000 to the home. police believe the victims were killed and the house set on fire. >> this is a crime scene. >> reporter: sources say the fire was set on the second floor in 10-year-old philip's bedroom, also the adults found nearby beaten and stabbed. police say this surveillance video shows wint running away to where detectives found their porsche abandoned and torched near the suspect's last known address in maryland. peter alexander,

nbc news, washington. >> reporter: this is tom costello. criminal experts say dna technology has come a long way since the o.j. simpson trial in 1995. today, criminologists can get a match from a sample as small as a fingernail or smaller. at the forensics lab in maryland, they test 2000 samples and dna has a long shelf life. >> it could last for a very long time. are we talking days, weeks, months? >> they can last for years of. >> reporter: they can last for years? >> certainly. >> reporter: am criminal can leave dna evidence at a crime scene without knowing it. skin cells left on a gas can, saliva sells on a wine bottle, blood, saliva and other bodily fluids. within a week police in washington quickly recovered dna on a pizza crust to quickly identify suspect daron dylon wint. joe ross is a specialist at the boston crime lab. >> when you take a sip of something or you bite something, you

are leaving saliva and your dna on that sample. typically, there will be a lot of dna in that. >> reporter: forensics experts say all they need is a sample that would fit on the end of a cotton swab. the chances that two people would share the same dna profile, one in several billion. the national dna database contains more than 11.6 million dna profiles from convicted felons and another 2 million profiles from suspects who have been arrested. when dna is identified at a crime scene, it is often entered into the fbi's combined dna index system or codis. if the codis software finds dna match anywhere in the country, police can identify a suspect. cutting edge technology that is changing the way police identify and track down violent criminals. tom costello, nbc news, beltsville, maryland. tonight, the governor of california has declared a state of emergency as crews race to clean up tens of thousands of gallons of oil that gushed into the waters off some of the most pristine shoreline in america when an underground pipe burst near santa barbara. tonight, nbc's miguel almaguer has a new

view that reveals the scope of the damage from the air. >> reporter: lester, good evening. this is one of the most spectacular, one of the most beautiful coastlines anywhere in the world. tonight, from 500 feet above the pacific ocean, you can see this area is clearly stained with oil. so far, the impact to wildlife has been mostly minimal, but you have to keep in mind this oil spill is only a few days old. environmentalists say the true impact on not just the environment but animals will take several days, if not weeks, to be realized. there is hope tonight that the weather is helping the cleanup. the waves and the wind have been relatively calm, keeping this oil mostly intact. it is certainly going to take some time to clean up the mess. so this spill wasn't a massive one. the impact on the environment may take months, if not years, to be realized. i'm miguel almaguer, 500 feet above the coastline. now, to my colleague, hallie jackson, who is

on the ground. >> reporter: today, a new vantage point from offshore looking toward where the oil spilled into the pacific from this culvert, a focus of the cleanup today. on the water both set booms to contain and absorb the spill as the response gets bigger. >> i see a big mess. we are fortunate the spill was contained rather quickly. unfortunately, oil did get into the ocean. >> reporter: in the ocean a sea lion swims through the slick and on land we're there as another is brought in. this is the first sea lion we have seen that may have been affected by the oil spill. crews will be transporting it to a stabilization center so they can look at how healthy it is and how to help it recover. some animals discovered dead but rescuers are hoping to save at least five pelicans they found. >> i anticipate we in the next few days we'll likely start seeing more. >> reporter: the spill raising questions about the company that owns the pipeline that burst tuesday, plains all american. federal records show 175 safety incidents

reported since 2006 causing nearly $24 million worth of property damage. issur company safe enough? >> again we're an operator who went through very detailed audits. we consider ourselves very prudent operators. >> reporter: the company says it is committed to doing the right thing in this cleanup. the spill is the first major problem with this pipeline since it was built in 1987. they estimate in the worst case snare crow that as much as 105,000 gallons of oil leaked, a fraction of the "the exxon "valdez" spill 11 million gallons and the deepwater horizon,

134 million gallons. this isn't a gulf size spill by any means but it has wrecked the place. >> reporter: the cleanup has moved into a 24-7 operation with crews recovering 8,000 gallons of oily water so far. still, a ways to go to get the beach looking like it normally does. postcard perfect. >> hallie, thank you. there are reports that isis has seized syria's last border crossing with iraq. isis now controls half of syria. territory which as of tonight includes a city of ancient treasures where isis is on the brink of erasing history. we get more from nbc's chief foreign correspondent richard ingle. >> reporter: another city fallen to isis. this time, it was syrian government troops who ran away as isis stormed into palmira. this isn't just another town on a map, it has lucrative oil and grass fields and it is a cradle of western civilization, one that's about to be rob the. palmyra had majestic ancient ruins, a preserved 2,000-year-old roman city. isis has promised to bulldoze it like it razed archaeological treasures in iraq, himrod, hatra and mosul.

isis believes these idols of pagan empires need to be eradicated. historians say it is a culture genocide. >> if we use palmyra, we use one of the top cultural sites in the entire middle east. watching isis' intentional destruction and blatant encouragement of looting at archaeological sites and cultural sites throughout their held regions has been devastating. >> reporter: it is not getting better. after taking the key city of ramadi in iraq last weekend, the terrorist sanctuary across syria and iraq is now larger than a small european country. the world awaits, expect horrible images to come from palmyra. more death, more culture being erase the. in an interview published today, the president says he does not think the u.s. is losing the war on isis and described the recent loss of ramadi as a quote, tactical setback, but frankly, lester, military

analysts have been speaking and military officials say the current u.s. strategy isn't working. >> richard, thank you very much. tonight, police in omaha, nebraska, are mourning the loss of one of their own, a police officer who recently became a mother for the first time. she was only a day away from taking a leave to be with a new baby until a confrontation put her in the line of fire. nbc's kevin tibbles has the tragic story. >> reporter: it was wednesday when officer kerrie orozco, a seven-year veteran of the omaha police force, was serving a warrant when the shooting began. >> officer down. >> officerors cowas shot and rushed to the nearest trauma center but doctors were unable to save her. police were attempting to arrest 26-year-old marcus wheeler, who they say was a known gang member on assault charges. he was also killed in the shootout, a semi-automatic handgun by his side. one of her partners remembers her.

>> she just saw people for who they were. the great thing was, she saw the good in all people. >> reporter: officerorsofficer orozco orozco's service went far beyond the police force. she coached baseball and volunteered her time with the girl scouts and the special olympics. celebrating the birth of her first child, a girl born prematurely, she and her husband were going to bring baby olivia ruth home today. she also had two young stepchildren. outside omaha police headquarters, they came all day, many of them strangers to pay their respects. >> i have four kids myself, and for them to have to miss their mom, it's awful. >> we knew she was present when she was there. >> reporter: on a downtown street, army veteran, ron ferguson, stood alone in tribute. >> sad. she lived a life for others and we'll all be together someday. >> reporter: officer kerrie orozco name will become the 25th engraved on a monument dedicated to those who have lost their lives here in the line of

duty. kevin tibbles, nbc news omaha. there is late word tonight from baltimore where the state's attorney says all six police officers charged in the death of freddie gray have been indied by a grand jury. gray's death, you'll recall, set off days of protests last month. prosecutors say his neck was broken during an arrest when he was handcuffed, shackled and placed head first into a place van without a seat belt. still ahead tonight, a warning about a new generation of pre-natal tests. everyone wants to note health of their unborn baby and new tests promise results earlier than ever, and what if those results are wrong?

we are back with an eye-opening report in our special series this week "would you want to know," the new medical frontier in dna testing. tonight, a closer look at the new kind of genetic test given to pregnant women to check the health of their unborn baby. a simple blood test promises more accurate results earlier than ever. there are growing concerns these tests have been oversold and misunderstood. our national correspondent kate snow reports. >> reporter: when stacy and lincoln chapman were expecting their first child, her doctor's office recommended a new blood test to check her unborn baby's dna. but then stacy's doctor called with terrible news. the test was positive for something called edwards syndrome. >> and then she explained to me that if the baby did

survive to full term he wouldn't last he would survive maybe hours, maybe days. >> reporter: you must have been devastated? >> mm-hmm, totally devastated. >> uh-huh, totally devastated. >> reporter: they made an appointment to terminate the pregnancy the very next day. >> we didn't want the baby to suffer. >> reporter: that night the doctor called back and suggested they should wait, and after eight long weeks stacy had an amniocentesis. and an even bigger shock, her unborn baby was fine. >> i still didn't believe it. i just didn't know what to believe anymore. like i knew, but i was afraid to believe it. >> reporter: how long did it take you to believe? >> until they put him in my arms, and they lifted him and showed him up above the screen. i just couldn't believe he was ours. >> reporter: these prenatal dna tests given as early as ten weeks are marketed for their accuracy. the maker of the test stacy used said in high-risk women a positive result for edwards syndrome is

right 97.6% of the time. several recent medical studies and investigation by the new england center for medical reporting casts doubt on the reliability of prenatal dna blood tests when they have a positive result for a disease. >> every day gets better. >> reporter: a study last year found a positive result on one popular test not the other statesy used could be wrong more than half of the time. leading ob/gyn dr. michael green said tests like stacy took are looking for the risk of disease, not actually diagnosing that a child will be born with it. >> reporter: before a woman makes an irrevocable decision she shouldn't make it based only on the screening test. it must be made on the diagnostic test result. >> reporter: the maker of the test stacy took agrees it is not a replacement for a diagnostic test such as cso or amniocentesis later in pregnancies.

other manufacturers recommend women have genetic counseling and the results be confirmed. stacy and lincoln's boy, sam, is a happy, healthy, 18-month-old. >> reporter: do you think about what might have happened? >> from time to time when he is playing or he does something funny. we'll say, can you believe that he's here and almost wasn't? >> reporter: the sweet face of a little boy showing the limits of the brave new world of genetic testing. kate snow, nbc news, providence, rhode island. we're back in a moment with the changes coming to an old family favorite, which is also the source of a lot of family arguments.

the national president of the boy scouts, former defense secretary, robert gates, says the organization's longstanding ban on openly gay scout leaders is no longer sustainable and called for a change in policy. just two years ago, the boy scouts ended the ban on openly gay youth as scouts but

left the adult ban in place. domestic violence charges have been dismissed against former baltimore ravens player, ray rice, caught on tape punching his future wife. at a new jersey casino. a judge signed after after he completed a pre-trial intervention program permitted in less than 1% of cases in new jersey. under the program, rice underwent anger management counseling and paid $125 in fines. some news that is frankly kind of ridic. you might need a teenager to fully get it. the scrabble dictionary is adding 6,500 new words including vape, emoji, and hashtag and ridic, short for ridiculous 1 and obbs and you obviously know what that's short for. and also you can continue to make words up like the rest of us. clowning around. why so many of us are wearing red noses this evening.

maybe you have noticed recently a lot of famous faces sporting red noses, all because of red nose day, a special event raring right here tonight on nbc, featuring a parade of stars having a laugh

for charity, including one that helped save the life of a young man you are about to meet. joe pryor has his story. >> reporter: if this run of the mill junior football varsity practice seems unusually riveting to the family of 15-year-old efron gonzalez, stop and consider what nearly slipped through their hands. >> when you almost lose your child, it changes everything. >> reporter: here, along the desolate desert grasslands of southeast arizona, medical care for kids was once scarce until a few years ago when a big, blue stranger pulled into town. dr. darlene milk now travels the region in a mobile clinic run by children's health fund. >> i love feeling like i'm in a place where not many people want to be, that there is something that i can do that makes a difference. >> reporter: no one is turned away, including efron's family in 2012 when they had no health insurance and he became very ill.

>> we literally were holding him up to walk to register in when she peeked out the window and she said, what's wrong? >> reporter: did you pretty quickly know what might be the problem? >> i did. >> reporter: doctor diagnosed ephron with diabetes and knew he had to get to the hospital immediately. >> i was weak, scared, just like my body was shutting down on me. >> reporter: ephron's family rushed him to an emergency room 75 miles away just in time. >> without the mobile clinic, he would have absolutely gone into a coma and i don't even want to say what the outcome would have been. >> reporter: efron is grateful for that doctor's office on wheels and now hopes red nose day will raise enough money to put more mobile clinics in places that need them. >> because one day you never know what could happen, and it saved my life. >> reporter: these days, it is not just the clinic that's going places.

joe fryar, nbc news, douglas, arizona. the red nose day special event with hosts, seth meyers, david duchovny and jane krakowski airs tonight. that's going to do it for us on this thursday night. i'm lester holt. for all o quite a commotion. right now at 6:00 a security breach, then this. a bay area man tased at l.a.x. we'll tell you why. good evening and thanks for being with us. i'm raj mathai. >> and i'm jessica aguirre. a uc berkeley student is at the center of a disturbing incident at l.a.x. police say a student, a ticketed passenger, breached security forcing them to stun him with a taser. jodi hernandez is live in dublin tonight where the suspect's

parents insist he's a gentle, well mannered young man. >> reporter: that's right, jessica. the suspect's parents live right here in dublin. his father tells me what they saw on that cell phone video is completely out of character for the uc berkeley student. he says the behavior simply doesn't match the son he knows. this cell phone video shows a 21-year-old east bay man breaking free as los angeles airport police try to handcuff him. >> he was shocked by a tsa officer and he was not cooperative. at that time the tsa officers asked airport police who were right near the screening area for help. >> reporter: passengers' cell phone cameras rolled as police followed christian james heintz through the terminal one officer eventually firing his