Three 19-year-old students who attended university with the surviving suspect in the April 15 bombings at the Boston Marathon have been charged in connection with the case.
Dias Kadyrbaev and Azamat Tazhayakov from Kazakhstan were charged on May 1 with conspiring to obstruct justice.
The third man, U.S. citizen Robel Phillipos, has been charged with making false statements to federal investigators.
Kadyrbekov and Tazhayakov are accused of trying to dispose of a laptop computer and backpack that belonged to bombing suspect Dzhokar Tsarnaev.
The affidavit says the two Kazakh nationals concluded from news reports that Tsarnaev was one of the bombers.
The pair allegedly removed the backpack, which contained fireworks emptied of gunpowder, from Tsarnaev’s dormitory room.
FBI agents were reported late last week to be searching in a landfill near the University of Massachusetts at Dartmouth where the suspects all went to school.
Kadyrbekov and Tazhayakov were detained by immigration services more than a week ago for violating their student visas.
Kadyrbekov and Tazhayakov face a maximum sentence of five years in prison and a $250,000 fine.
Phillipos faces up to eight years in prison and a fine of $250,000.
All three are scheduled to appear in court later on May 1.
Three people were killed and some 260 injured in the two explosions in Boston.
One suspect Tamerlan Tsarnaev was later killed on April 19 following a gunfight with police.
His younger brother Dzhokar was subsequently apprehended after a massive manhunt that closed down Boston for a day.
He is now in a prison hospital recovering from injuries he sustained in shootouts with police.