we know at this time two of them went in immediately when they arrived at the building and heard the gunshots. immediately went in the building and started giving lookouts and passing information on. once they got inside the building, the thought they put into ensuring other teams could get in, that other teams could get in quickly, that other teams could move around safely was unbelievable. i don't have the exact time it took before the final engagement. that will come much later after all the forensics is done. i can tell you there was multiple engagements with the suspect with multiple different agencies before the final shots were fired. i would say there was a pretty good period of time with multiple engagements before that. i can't give you an exact time. i'll take one more. >> was it more than a half an hour from start to finish? >> yes, i would say more than a half an hour. >> more than an hour? >> i don't believe it was more than an hour. more than a half an hour. again, we won't know that until