Then, in 2008 or 2009, Tamerlan met Misha, a slightly older, heavy set, bald man, with a long reddish beard. Khozhugov didn't know where they'd met but believed they attended a Boston-area mosque together.
Misha was an Armenian native, and a convert to Islam and quickly began influencing his new friend, family members said.
Once, Khozhugov said, Misha came to the family home outside Boston and sat in the kitchen, chatting with Tamerlan for hours.
"Misha was telling him what is Islam, what is good in Islam, what is bad in Islam," said Khozhugov, who said he was present for the conversation. "This is the best religion and that's it. Mohammed said this and Mohammed said that."
The conversation continued until Tamerlan's father, Anzor, came home from work.
"It was late, like midnight," Khozhugov said. "His father comes in and says, 'Why is Misha here so late and still in our house?' He asked it politely. Tamerlan was so much into the conversation he didn't listen."