warnings against self-incrimination. tried in a is civilian court or military tribunal. before we go there let s start with the latest from the scene and why craig and a i immediately recognized the pressure cooker bombs. we have seen them many times before. here is craig s crime time report. reporter: the quiet streets of watertown became a war zone as the boston marathon bombers made their last stand here. homes can be seen riddled with bullets. this black mark from a pressure cooker bomb, one just like the one that was used to kill three people, wounding 180. there was two cars. black suv and a green looked like honda accord. had some bags that he was one of the guys was lighting things and throwing them. had fuses and they would explode but you also lots of shoot going on. brothers dhokhar 19 and 26-year-old tamerlan starr tsarnaev add to the marathon death toll, killing police officer shawn collier in cold blood. the police officer that was killed you said it was