CNN Early Start With John Berman and Christine Romans March 12, 2015 08:45:00
Deborah feyerick. >> reporter: john 911 calls saying officer down. officer down. all units. it was m.i.t. police officer sean collier. he was executed on the m.i.t. campus. prosecutors showed video of two men they identify and tamerlan and dzhokhar tsarnaev walking to the cruiser and leaning in. you can see the brake lights on the car getting bright. the two brothers for a full minute standing there before bolting. one person on campus said he heard loud noises. there was a cruiser in the vicinity. sean collier did not respond to radio calls or cell phone calls. he had been shot multiple times...
Source: archive.org