about an ar-15. what happened to that gun? did he have that, too, or are police taking that back? >> there are actually questions whether he was armd with an ar-15, whether there was one there or that belonged to another officer there who engaged the suspect. we have learned from a law enforcement source that he rented and returned an ar-15 before the shooting, we believe, at a gun range. as far as imhim being armed with an ar-15, that's still a question about whether, in fact, that happened. >> rented? very interesting. >> i didn't know you could do that, but apparently you can. >> so many questions about his past. there are many, many questions today about how this man had access to the building. we've been told that he drove on, using his military security clearance, that he did have at the time, as a contractor. there are questions whether that clearance, background checks might have been tight enough, might have been stringent enough. let's go now to cnn reporter