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.
16.15 (11.15) Tom Parfitt, our Moscow correspondent, has more on Dzhokhar's social networking site VK- VKontakte (In Contact), in which he says he speaks English, Russian and Chechen.
The home page says he was at Cambridge Ringe and Latin School in the 2011 school year, and that in 1999-2001 he attended School No. 1 in Makhachkala, the capital of the Russian republic of Dagestan, on the coast of the Caspian.
He lists his World View as Islam and his “Personal Priority” as “Career and money”.
He is a member of two groups in VKontakte for Chechens, and three of his five “noteworthy pages” are Islamic-themed.
The latest post on the account – uploaded on March 19 - is a video called “The bro did good” and features a young man sitting in the back of a car and smiling as he mimics several different accents from the Caucasus region, and recounts stereotypes about each ethnic group.
Tsarnaev adds his own joke about three nations of Russia’s North Caucasus, all plagued by crime and Islamist violence.
“In school they give a riddle… A car is driving. A Dagestani, a Chechen and an Ingush are sitting in it. Question: Who’s driving? Maga [Magomed] replies: The police.”
A video expressing sympathy with rebels fighting in Syria, and a clip of a Kuwaiti sheikh talking to a blind boy who memorised the Koran also feature on Tsarnayev’s VKontakte page.
Abusive messages from other users began to appear on the page in both English and Russian on Friday.
16.11 (11.11) Apparently seven miles of air space have been shut. Police helicopter still in the air.
16.08 (11.08) A woman understood to be the mother of the Tsarnaevs was arrested last year for shoplifting at Lord & Taylor, the same department store that was cited earlier this week as having helped in the investigation to identify them thanks to their CCTV footage.
A woman was also pictured being escorted out of the Tsarnaevs' house earlier today - her identity was unclear but she was older.
Members of the FBI, State Police, Boston Police, Cambridge Police and other law enforcement agencies take away a woman near the home of suspect 2 on Norfolk Street to talk to her