(CNN) - (CNN) -- Three friends of Boston Marathon bomb suspect Dzhokhar Tsarnaev have been jailed on charges they tried to throw investigators off Tsarnaev's trail, federal prosecutors announced Wednesday.

Two of them, Azamat Tazhayakov and Dias Kadyrbayev, were already in federal custody on immigration charges, their lawyers told CNN. Both are from Kazakhstan and had student visas.

The third, Robel Phillipos, is a U.S. citizen. Tazhayakov and Kadyrbayev are charged with obstruction of justice, while Phillipos is charged with lying to federal agents probing the bombing, according to court papers.

They made their first appearance before a federal magistrate Wednesday afternoon, when they were read the charges against them and informed of their rights.

Latest on the investigation

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