(CNN) — Two classmates of Boston Marathon bomb suspect Dzhokhar Tsarnaev and a third person face federal charges in connection with the April 15 attack, federal law enforcement sources said Wednesday.
Boston police announced the arrests Wednesday morning, adding that there was “no threat to the public.” They were expected to appear before a federal judge Wednesday afternoon, U.S. government sources said.
The classmates — Azamat Tazhayakov and Dias Kadyrbayev — are both from Kazakhstan and had been in federal custody on immigration charges already, their lawyers told CNN. The third person arrested is a U.S. citizen.
The Kazakh students face charges of making false statements to investigators and conspiracy to obstruct justice, according to a federal law enforcement source with firsthand knowledge of the investigation.
All three are accused of removing items from Tsarnaev’s dorm room at the University of Massachusetts-Dartmouth after the bombings, a law enforcement official who has been briefed about the arrests said.
Law enforcement officials believe they helped destroy evidence that might further implicate Dzhokhar Tsarnaev in the bombing by disposing of fireworks and his laptop, a U.S. government official said.
Two U.S. government officials said the charges involve illegal actions after the bombing. One official said Dzhokhar Tsarnaev contacted the three after FBI agents released photographs of Tsarnaev and his older brother Tamerlan and asked them to dispose of the items. The suspects said they did not know the significance of what they were doing, the official told CNN.
Another federal law enforcement official said two of three lied to the FBI when asked about whether they had seen the suspects or knew of their whereabouts after the bombings.
That official said the suspects threw out backpacks of fireworks from the dorm room, leading to a two-day search of a New Bedford landfill last week.
Alan Dershowitz, a prominent defense attorney and Harvard law professor, said called the obstruction charge “weak,” suggesting it was meant to pressure the suspects into providing more information on Tsarnaev.
“If that’s the best the feds have now, then they’re just squeezing,” Dershowitz told CNN. “It doesn’t sound like they have very much new here.”
Two bombs exploded in the crowd gathered near the finish line of the Boston Marathon, killing three people and wounding more than 260. Federal agents blame the Tsarnaev brothers of carrying out the attack.
Tamerlan Tsarnaev died after a shootout with police on April 19, while Dzhokhar Tsarnaev was wounded but survived.
Tazhayakov and Kadyrbayev appear in a photograph with Dzhokhar Tsarnaev taken in New York’s Times Square during an earlier visit. They were taken into custody last month on charges that they had violated the terms of their student visas and had already been questioned by investigators on April 19, hours before Tsarnaev’s arrest, Kadyrbayev attorney Robert Stahl told CNN.
Federal law enforcement sources said at the time that the Kazakh students were being detained “in an abundance of caution” because authorities wanted detailed information on the Tsarnaevs’ movements in the weeks and days before the attack.