he may have been familiar with. and one of the questions, obviously, is was there a workplace issue? was there something that set him off that brought him there on monday to start shooting. that is still something they're struggling with. they don't quite note how to put it together. but at this point, it can loos like he goes through the building, shooting randomly. goes down to the first floor. then back up. all of this goes down about 30 minutes before the authorities are able to bring him down and shoot him dead on monday morning. and like i said, right now, it's still very much an effort to try to figure out what might have motivated this on monday morning, mike. >> evan, there is some reporting perhaps he was -- had he worked with some of those individuals that he was targeting or that he shot. is that true? did he actually know the people that he was shooting? >> that is still an open question. the fbi is going through, like i said, interviewing witnesses. as far as we can tell, they still are puzzed by the idea of how he started doing this on the