Here’s a link that will take you to the video.
The Barghouti kid said that the police were waiting outside because they couldn’t get in through the main door (I imagine it was chained)...but they finally broke through, and that is the point in the video where you see all the police run at once toward the building.
http://www.cnn.com/2007/US/04/16/vtech.witness/index.html
ABC News reports “a disturbing note” was left behind.