15.50 (10.50) There are reports of shots being fired near Watertown.
Update, 10:37 a.m. EST: TheDC’s Patrick Howley has put together all we currently know about Tamerlan Tsarnaev, the now-dead Boston Marathon bombing suspect. He “was a student at Bunker Hill Community College and a Golden Gloves boxer who trained at Wai Kru mixed martial arts gym in Boston and competed in a national Golden Gloves competition.” He also described himself as a “very religious” Muslim. Read the full story here.>/P>
Update, 10:20 a.m. EST: The now-deceased bombing suspect, Tamerlan Tsarnaev, apparently posted a video touting an Al Qaeda-linked “prophesy.” You can watch it here.
Update, 10:03 a.m. EST: Buzzfeed reports that high school classmates of at-large Boston Marathon bombing suspect Dzokhar Tsarnaev, 19, are shocked by today’s news. The former classmates describe Dzokhar as a “sweet, sort of quiet” boy with a number of friends at the prestigious Cambridge Rindge and Latin School.
Update, 9:37 a.m. EST: Anzor Tsarnaev, the father of both Boston Marathon bombing suspects, spoke with The Associated Press by telephone from the Russian city of Makhachkala on Friday: “My son is a true angel. … Dzhokhar is a second-year medical student in the U.S. He is such an intelligent boy. We expected him to come on holidays here.” Read the full AP story here.
Update, 9:14 a.m. EST: The Weekly Standard reports that wanted Boston Marathon bombing suspect Dzhokhar Tsarnaev received a city scholarship from Boston in 2011, and attended the same prestigious secondary school as actors Matt Damon and Ben Affleck.
Update, 9:07 a.m. EST: It appears Boston PD was relaying threats posted by this Twitter account . … It is possible but unconfirmed that someone impersonating Boston Marathon bombing “Suspect 2″ Dzhokhar Tsarnaev created the account on Twitter one hour ago, tricking Boston police.
5.55 (10.55) Couple of bits that may have got lost in the shuffle here. Anzor Tsarnaev earlier urged his son Dzhokhar to turn himself in: Quote Give up. Give up. You have a bright future ahead of you. Come home to Russia. He warned however if he is killed, "all hell would break loose."
14.50 (09.50) Larry Aaronson, a teacher at Ringe and Latin school, says not only did he know Dzhokhar, but he took photographs of him on the wrestling team. He writes on Facebook: Quote I cannot believe he was capable of such a heinous crime and of so many murders. Truth be told he came from the war zone deep inside Chechnya like about 5 or 6 years ago... with his entire family... When I was quoting that the war has come home yesterday to everyone, I did not mean it like this!!!! As the old hebrew expression goes. You got to be f****** kidding me... (BUT THEY ARE NOT)
15.49 (10.49) A photograph of Dzhokhar Tsarnaev wrestling has been posted on Twitter. 
16.04 (11.04) Dzhokhar Tsarnaev at his graduation from Cambridge Rindge and Latin High School 
15.04 (10.04) The identity and photograph of the MIT police officer has been released. He is Sean Collier, 26, of Somerville. 
14.47 (09.47) Ruslan Tsarni, the brothers' uncle, said that he received a call from Tamerlan last night having not spoken to him for a couple of years, in which he asked for forgiveness.