♪ you want the craps we hit the blackjack ♪ this is "nightline." >> tonight, christmas nightmare. >> i saw one guy being dragged away with blood on his face. >> an apparent terror attack in berlin, a truck plowing into a crowded christmas market killing at least 12 and injuring over 45. what investigators are learning about those believed to be responsible tonight as authorities ramp up security here at home this holiday season. plus passengers. >> do you know what's going on? >> jennifer lawrence on making her new outer space adventure with chris pratt. >> once i got out of the suit, lift your arms and pretend you're floating. i'm like, that's just not possible. >> the secret insecurities of an a-list actress. >> took you long enough to ask. >> what she really meant when she spoke out about the election results. >> it wasn't a normal election

and i had a lot of feelings. and i don't know her. ♪ diva emotions run high as mariah carey puts demi lovato on notice for throwing shade on social media. but first the "nightline 5." >> time's almost out to give some sparkle with jcpenney. dash in to save on stunning diamond areaings. save an extra 20%, earn $15 in j jcpenney cash for every $50 you spend. jack up the savings. that's getting your penny's worth. >> press "clean" and let roomba help with everyday masses. roomba cleans up pet hair and debris for up to two hours which means your floors are always clean. you and roomba from i-robot. better together. >> number one in just 60 seconds.

good evening and thanks for join is. tragedy in berlin. what the white house is calling an apparent terrorist attack. tonight we have harrowing images and eyewitness accounts from the scene. all this in the wake of other at attacks throughout europe, including the assassination of a foreign diplomat in turkey and a shooting at a mosque some switzerland as information is coming in about who was in the truck that barreled into that crowded christmas market in berlin. catastrophe in the christmas market. a truck plowing into unsuspecting shoppers in the heart of berlin just six days before christmas. >> it went just past me, past my girlfriend. >> reporter: killing at least 12 and injuring more than 45. >> it was relentless, it didn't seem to stop. >> reporter: 8:14 p.m. monday night, police say the driver of

this large delivery truck carrying steel supports jumps the curb at a high rate of speed and plows into the square, tearing through popup shops and crowds for a distance of at least 50 yards. >> it missed me by three meters, missed her by five, it came in through the entrance, hit the sides of the barriers, and then carried on past us. >> reporter: first responde ere descending on the horrifying scene. what was just moments ago a hub for holiday cheer now a triage unit. emma rushton was there. she spoke so "the daily mail." >> it was just crashing through people, crashing through the huts, it pulled the lights down. >> it's really disconcerting to think that the idea somebody could drive a truck into a market where you're shopping for christmas presents or buying a christmas tree is unbelievable. >> reporter: the market seen here in these earlier photos was considered to be the equivalent of new york's times square. berlin now a city on high alert

as police search for any motive investigating an act of terrorism. >> i saw one guy being dragged away with blood on his face. i helped several other people lift the side of one of the stalls up so that they could pull two other people out. >> reporter: the truck had polish license plates. berlin police suspect it was stolen from a polish building site. officials say there were two people in the truck, one who died in the crash and is confirmed to be a polish citizen. another fled the scene and has now been captured. berlin police believe he was driving the truck. >> as the police did a background investigation on the driver, they then would go through and have him sequentially go through the last 24 hours. you would go through all of those steps with him. then you would eventually get to, if you believe you're now into the realm of terrorism, of what was the drive, what was the motivation? >> reporter: bbc's jenny hall was on the scene. >> very, very early stages in our investigation.

very few details to be gleaned at this stage. many, many questions. what we do know, of course, is that earlier this evening, hundreds, thousands of people came to this, one of berlin's biggest christmas markets, to enjoy the festivities. instead, they witnessed scenes of horror. >> we know that in general, markets and christmas markets have been seen as a possible target by the intelligence community. >> reporter: european security services issued several terrorism alert warnings after a terrorist plot targeting christmas markets was uncovered in another german city. >> anywhere where large numbers of people gather, you certainly have the potential for one of these types of attacks. >> that's what concerns law enforcement officials. the ease with something like this can be done. >> reporter: days ago german authorities reportedly arrested a 12-year-old boy suspected of plotting a nail bomb attack the

a christmas market in a southern german city. authorities declined to talk about the case publicly because of his age. it's the second time this year a truck has become a makeshift weapon of mass destruction. in july, that attack in the french resort town of nice. >> it was sheer terror. >> reporter: when a man claiming allegiance to isis plowed a truck through a crowded avenue as people celebrated france's national holiday bastille day. >> i did see it hit a few people. and then there were a few people lying on the ground. >> we started running. see people ducking, get into doorways, hide. there was the sound of shooting in the air. >> reporter: a trail of bodies would be left in its path. 85 people would die from the attack. children among the victims. more than 200 left injured. tonight, according to the french interior minister, france is now beefing up security at their own

christmas markets. >> when you have an attack like which occurred in berlin, you then start looking at other vulnerable sites. in other words, other christmas markets or markets in general. so you now have to look at each market individually and figure out, what's the best thing can we do? >> reporter: and here at home, the white house is condemning what they say appears to be a terrorist attack. president-elect trump releasing this statement. calling it a horrifying terror attack in berlin. isis and other islamist terrorists continually slaughter christians in their communities and places of worship as part of their global jihad. for now, authorities have not tied the event to isis. for weeks now security officials warning americans about potential holiday season incidents similar to today. the fbi and homeland security officials issuing a bulletin warning that holiday celebrations lasting through the inauguration could be targeted. in new york city tonight, heavily armed police officers

are on guard at christmas markets. even though they don't have evidence of a specific plot. >> you just have to be aware that we live in a dangerous world. we want people to go forward, enjoy the christmas season. but obviously be aware of the fact that in this day and age, something untoward could happen. >> reporter: the nypd has revved up security since thanksgiving after isis released a message featuring a picture of the new york parade calling its followers to use speeding vehicles to attack outdoor events. in response nypd security officials dispercented themselves among paradegoers, setting up sanitation trucks with sand and cement blockades to prevent a truck attack. >> the idea that you would attack something that occurs every year, that's special to everyone involved it in, giving, caring for others, if they can mess that up and cause us to change our way of life, then in

their mind, they have succeeded. >> reporter: as dawn breaks in berlin, a city in shock and mourning, a memorial service will be held tomorrow to honor the victims. our thoughts tonight are with the people of berlin. and we'll continue to follow this story as it develops tomorrow on gma. next, a woman who can always make us smile. jennifer lawrence, why she says she's done performing her own stunts.

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by most accounts, jennifer

lawrence has had a dream career. an academy award-winning actress, she's the face of several blockbuster films and franchises. but she also spends time on independent passion projects. a balancing act she says is harder than it looks. here's abc's michael strahan. >> hello! anybody here? >> do you know what's going on? >> reporter: it's not a secret jennifer lawrence can give an out of this world performance. in her new movie "passengers," proves just that. >> it's the most original story i've seen in a really long time. >> this can't be happening, we have to go back to sleep. >> reporter: in the thought-provoking sci-fi thinner, aurora embarks on a 120-year voyage to a distant colony planet. she and fellow passenger jim are supposed to be hibernating. but wake up too soon. >> we woke up 90 years too soon. >> reporter: with costar chris

pratt, the a-list duo teaming up in this physically demanding movie. >> i can't complain because chris had to do most of the space anti-gravity stuff where he's pretending there's no gravity when he's wearing a 75-pound suit. and i'm like, i was wet 12 hours a day for a week. so i don't feel good complaining. i couldn't physically do the space stuff. once i got in the suit they were like, lift your arms and pretend you're floating. i was like, that's not possible. chris would have to lift his arms up and pretend it was zero gravity. they wanted me to do that and it was like, no. >> reporter: pratt showing off his battle wounds on instagram. >> do you like that physical? some of your roles have been physical. >> no, once i finished "hunger games" i was done doing stunts. i don't like them. they're strenuous, they're stressful, i'm very paranoid so i'm afraid i'm going to get hurt. >> but you're so good. >> i'm saying that in case

somebody wants to cast me for an action movie. >> wow. >> reporter: pratt and lawrence prove to have good chemistry on screen, and a better sense of humor off. >> i got to work with her, and now she's my best friend. >> we're mortal enmeals. >> no. >> reporter: pratt posting a series of prank instagrams, cropping lawrence out of several photos during their press tour. >> hello. >> reporter: on screen, lawrence and pratt find romance during their travels. >> you two look fine this evening. >> we're on a date. >> very nice. >> you and chris are literally in this movie together, on screen, hours. >> yeah. >> and that's a lot of pressure. >> when you watch it you really realize, it's prime alley just us. i've never been in a movie like that. >> this movie made me think so much, if i would be able to pack up like your character did and move away and leave behind my family and friends. do you think that's something you'd be able to do? >> i can't see just saying

good-bye to everyone i know and love and just peacing out. by the time you land, everyone you know is dead. so that's really intense. i think the journey sounds amazing. if i could bring people, maybe i would. >> if there's one person you had to be stuck with on a ship for 90 years, who is it? >> i have experience with kind of being stuck on a ship with chris pratt. we were stuck on a set over 16 hours a day for four months in atlanta together. that worked out great. >> reporter: j-law's journey has been a fast and steady one, striking box office gold, starring in oscar-winning films like "silver linings playbook." >> come on, please! >> calm down, crazy. >> i volunteer as tribute! >> reporter: it was the hunger game" franchise which made the 26-year-old actress a household name. >> because you're not involved with a franchise anymore, do you feel more freedom in the roles? you feel you have more time? >> i feel more freedom, i feel more pressure. before it was finding one movie a year in between franchises.

now it's like i feel like everything that comes out, it's really my decision, there's a lot of the weight. >> it's like, the first one i didn't like, the second one -- >> here comes "the hunger games" movie and you'll forget about it. now the safety buffer is gone. >> that's surprising to hear because i think most people would look at you and they would say, boy, look at her, she has such confidence in herself. everything she touches is successful. she doesn't get nervous at all, she doesn't have any stress about the movie that she chooses because she's just going to knock it out, people are going to go see it. >> no, there's a lot of -- first of all, those people are crazy. where are they? no, it's a lot of pressure. i definitely feel it. it's hard to strike a balance. >> reporter: the a-lister finds that balance when she speaks her mind. expressing her opinions and using her public platform to discuss topics celebrities shy away from. >> the only times i've spoken up

about things is when i don't see another option. >> reporter: in this post-election later, "do not let this defeat, youlet this enrage you. let it motivate you. let this be the fire you didn't have before. if you are an immigrant, if you are a person of color, if you are lgbtq plus, if you are a woman, don't be afraid, be loud." >> it was important for me to voice myself. this election, it was really powerful. it was really big. it had a lot of feelings. >> you seem to have an opinion, yet you seem to be able to fit it within your career without some of the worry i think other people have. >> i mean, i do have the worries. there's just some time -- i definitely do not judge anyone for never wanting to talk about issues or never wanting to -- because it's really hard. not everyone's going to agree with you and people are very vocal. and my job depends on everyone going to see my movie, not just people who agree with my

opinion. i didn't mean to speak only to people who voted for hillary, i meant to speak to the divide in america. i think for any presidential candidate, being very extreme is scary. left or right. an extreme candidate is scary because it can divide the country. that's scary interior politics aside, lawrence continues to charm her fans around the world. and while she has tackled a wide range of roles, lawrence said this project is unlike anything she's ever done before. >> i think the depth and the story, i think it's going to surprise people the same way it surprised me. >> reporter: for "nightline," i'm michael strahan in new york. next -- ♪ >> demi lovato had some harsh words for a fellow pop star. but nobody can shake it off like mariah carey. her biting response.

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finally, a lesson for young pop stars. when you sit at the feet of a giant, you're bound to catch some shade. >> what do you think about people referencing i don't know her all these years later? >> i still don't know her. >> reporter: from tmz's cameras to appearances on "watch what happens live" with andy cohen -- >> i don't know her either. >> the famous phrase i don't know her taking on a life of its own. is it possible two mega stars like mariah and j. lo have never met? apparently so. >> do you know j. lo at this point? >> i'm forgetful. ♪ why so obsessed with me >> reporter: fans obsessed with drama. now t-shirts, hoodies, even pins with the phrase. mimi seems to shake it off. ♪ shake shake shake >> reporter: except when it comes to demi lovato who stood up to m.c. on instagram.

>> she said, mariah's a legend and she's so talented but she disses people, it's nasty the way she treats jennifer. what would you say to demi? >> i don't know her either. i wouldn't say anything to her. she should come up, introduce herself to me, say, here's my opinion, what do you think about it? that's how you handle [ bleep ], okay? >> reporter: feuding divas are fan fodder. one of them taking to twitter writing, all i want for christmas is for mariah carey not to know me either. another, omg, yas, mariah cara. j. lo isn't the only one. she says she doesn't know madonna. >> never had a conversation. >> she doesn't know miley. >> i think we met if a bathroom, i don't know. >> reporter: she knows beyonce. and how about britney spears? >> what about britney? >> i love britney. >> they loves britney. thank you for watching abc news. as always we are online