wake of killing three people in the boston marathon and a police officer at mit. there was some sort of incident near mit last night. the security officer approached these men and ultimately was killed. police say these two brothers killed them. they wound up carjacking a man, taking his s.u.v. that man runs into a 7-11 and says these guys are trying to kill me, help, help. they take off in the s.u.v. a police chase ensues. you heard griff jenkins talk about some of that. a shootout, they're throwing grenades out of the car. ungeier is exchanged and the older brother with the black baseball cap on the right side of your screen is killed. ever since then they've been trying to track down the younger brother, and they're very interested in what he has to say. our own bret baier earlier shared information from sources at the national counterterrorism center indicating that at least one of these brothers may have posted videos on line, praising al-qaeda and its war on the