we will get straight to mark bergen after this quick break. our reported that covers tech and youtube. we will be right back. ♪ mark: i'm mark crumpton in new york. we are staying on developing news. nbc news is reporting at least seven people have been sent to ofal hospitals after reports an active shooter at youtube headquarters in san bruno, california. northern california stamford hospital confirms it has received at least four people but no word on their conditions. a representative for the san bruno police department says the campus is being evacuated. you are seeing live aerial footage right now. one employee tweeted that he and other coworkers were barricade inside the room. that employee has since confirmed his safety. san bruno police sent out a tweet warning residents to stay away from the area. google says it is coordinating with authorities on the situation. california congresswoman nancy pelosi tweeted she is watching developments and thanks first responders. the white house press secretary sarah huckabee sanders says president tr

emily: mark bergen, thanks so much.u will continue to report on this story and we will hear more from you. reports that the youtube shooter posted online rants about the company have people asking if that should've raised a red flag. my next guest has made a career of tracking illicit content online. it is the focus of our latest installment. i want to bring in a senior advisor to the contrary extremism technology project. he has worked with companies like microsoft. his work has led to the detection of child pornography and extremist videos. i want to hear your reaction to this shooting. at the being of the situation, we didn't know what happened. now we have a full or picture. -- a fuller picture of the story. what's your take on this? >> there is no doubt there are complex issues when you deal with platforms of the size of facebook and youtube. youtube has hundreds of hours uploaded every minute. there will be complex issues. wehave always known that and have tried to contend with that. our point has been that while

i spoke with mark bergen the day after the shooting to talk about the larger implications. say she was upset at youtube's policies, and we have seen from some of her videos that were taken down yesterday, her website, she was a strong vegan rights activist. she posted a lot of videos about animal rights, some of them looked like grotesque images of animals being tortured. her claim is something similar that we have been hearing from youtube creators have been seeing less and less ad inventory, some claim youtube is hurting their livelihoods. that is the point she has made. it is an extreme example and it seems like this response was probably driven by mental health issues. emily: what about how google and youtube are responding to this, given that she got into a private patio at you to pay -- at youtube headquarters, which presumably there is badge access. somebody with a gun shouldn't have been able to get inside? mark: we don't know if they're changing their policy. it's likely they will. companies like youtube, google, facebook are structured like college campuses. they

we do have mark bergen at the san francisco bureau and joins us on the phone.what you have heard right now and what we are seeing as far as the media coverage in san francisco. mark: we don't have a lot of information right now. the company has not commented. parent youtube's company, has not said anything to their employees. we have seen people post on twitter saying they are safe and evacuated the building. recently theyd are responding to the active shooter and advised people to stay away from the intersection. joe: just for context, youtube's headquarters are totally in a different location than the main google office. mark: they are closer to the city. san bruno is closer to the san francisco airport. beat is where youtu operates independently. julia: what you are looking at now is live pictures of san san francisco. an overview of youtube's headquarters. we were just showing you pictures of individuals leaving the campus area individually being searched by police on the scene because of an active shooter at the youtube headquarters. scarlet: we don't know

emily: thank you for that update, mark bergen. are getting ready for the two other big names reporting this week, facebook and twitter will be out with their numbers on wednesday. twitter at 8:00 a.m. easter and facebook after the closing bell. i want to bring up derek and selina wang. will we see the impact from this scandal? >> people will be looking at changes facebook made earlier than march, causing problems of the -- just features of people issues people see on their site, such as fake news. should be able to his the impact of that this quarter. is that affecting engagement or ad revenue? we are not sure yet and there is another aspect of this, which is engagement. facebook users are spending less time on faith and that is a huge issue if it is not done by facebook by design. emily: numbers were also dragged down. how much of a impact will we see from twitter by the ancillary privacy concerns? >> twitter has managed to stay out of the limelight because of the way the platform was ca created. they are already selling to third

emily: all right, mark bergen, thanks so much.u will continue to report on this story and we will hear more from you. reports that the youtube shooter posted online rants about the company have some people asking if that should have raised a red flag. my next guest has made a career of tracking illicit content online and developing technology that helps identify things like child pornography and extremist videos. it's technology that could be used to create socially responsible networks online. it's the latest installment in the socially responsible network series. i want to bring in dr. hany farid. his work with companies like cep and microsoft has led to the detection and prevention of the uploads of millions of images of child or not her feet, as -- child pornography as well as extremist videos. i want to hear your reaction to this shooting at you to -- at youtube. for so many minutes at the beginning of this situation, we didn't know what had happened. now that we have a fuller picture of the story. what's your take on this? d

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