The evolution of Tamerlan Tsarnaev from aspiring Olympic boxer to apparent self-radicalized jihadist may have been influenced by a friend in Cambridge, Massachusetts.

"It started (in) 2009. And it started right there, in Cambridge," Tsarnaev's uncle Ruslan Tsarni said from his home in Maryland.

"This person just took his brain. He just brainwashed him completely."

http://www.cnn.com/2013/04/24/us/boston-brainwash/index.html?hpt=hp_t1