Boston Marathon bomb suspect Dzhokhar Tsarnaev's friends plead not guilty

Three friends of Dzhokhar Tsarnaev pleaded not guilty Friday to charges of impeding the federal investigation into the Boston Marathon bombing.

Three friends of Boston Marathon bombing suspect Dzhokhar Tsarnaev pleaded not guilty Friday to charges of impeding the federal investigation into the bombing which killed three people and injured 264 in April.

According to the indictment filed Aug. 29, the three 19-year-olds, Dias Kadyrbayev, Azamat Tazhayakov, and Robel Phillipos, school friends of Tsarnaev's at the University of Massachusetts at Dartmouth, all helped remove a backpack containing fireworks and a laptop from Tsarnaev's dorm room, after he texted Kadyrbayev a request to "go to my room and take what's there." 

Kadyrbayev and Tazhayakov were roommates who allegedly decided together to pitch the objects into a dumpster, and then watched its contents disappear into a garbage truck the next morning. According to the Boston Herald, both face up to 25 years in prison or deportation to their native Khazakstan, for destroying evidence in order to hinder the FBI's investigation. Phillipos, an American, faces up to sixteen years in prison for two counts of lying to investigators.

Prosecutors told AP that they planned to present about 20 witnesses in a trial that could take two weeks. A trial date has not been set.

Meanwhile, the in-laws of Tsarnaev's late brother Tamerlan, who died in a police shootout after the bombing, answered questions Thursday before a grand jury in Boston. The lawyer representing the family of Katherine Russell, Tamerlan Tsarnaev's widow, declined to tell CNN about the hearing.

Dzhokhar Tsarnaev, who could face the death penalty, continues to await trial.