The number of people potentially embroiled in the Boston Marathon bombings case grew Wednesday to include friends of surviving suspect Dzhokhar Tsarnaev.

Not much is known yet about the three 19-year-old men -- Azamat Tazhayakov, Dias Kadyrbayev and Robel Phillipos.

But here is what CNN has learned so far.

All started at the University of Massachusetts-Dartmouth in 2011, along with Tsarnaev.

Each is accused of removing items from Tsarnaev's dorm room after the April 15 attack, which killed three people and wounded more than 260.

Robel Phillipos

Unlike Tazhayakov and Kadyrbayev, Phillipos is a U.S. citizen.

Like Kadyrbayev, he is not a current student at the University of Massachusetts-Dartmouth.

Phillipos attended high school with Tsarnaev at Cambridge Rindge and Latin School in Cambridge, Massachusetts, where they both live.

A yearbook photograph shows a smiling Phillipos. Almost directly in front of him, Tsarnaev stares at the camera -- his hand gently resting under his chin.

Phillipos is charged with lying to federal agents investigating the bombing. He faces up to eight years in prison if convicted, along with a $250,000 fine.

A friend described Phillipos as a "good kid."

"He went to school, never got in trouble, took care of his mom," James Turney told CNN affiliate WBZ. "He was not really outgoing, stayed in the house a lot, did homework, got good grades."

Phillipos plays basketball and doesn't have "any anti-American thing about him," Turney said.