A college friend of Boston Marathon bombing suspect Dzhokhar Tsarnaev was convicted Monday of impeding the investigation into the bombing.

Azamat Tazhayakov was charged with obstruction of justice and conspiracy, with prosecutors saying he agreed with a friend’s plan to remove Tsarnaev’s backpack containing altered fireworks from his dorm room a few days after the 2013 bombing.

His trial was the first stemming from the bombing, which killed three and injured more than 260 near the marathon’s finish line. Tazhayakov’s mother sobbed loudly and rocked in her seat as the jury announced the guilty verdicts, which it reached on the third day of deliberations.

Tazhayakov’s lawyers argued that it was the other friend, Dias Kadyrbayev, who removed the items from the University of Massachusetts-Dartmouth dorm room and then threw them away.

Prosecutors told the jury that both men shared in the decision to remove the items and get rid of them to protect Tsarnaev. Kadyrbayev faces a separate trial in September. A third friend, Robel Phillipos, is charged with lying to investigators.

During Tazhayakov’s trial, FBI agents testified that Tazhayakov told them he and Kadyrbayev decided to take the backpack, fireworks and Tsarnaev’s laptop computer hours after Kadyrbayev received a text message from Tsarnaev that said he could go to his dorm room and “take what’s there.” The items were removed hours after the FBI released photos and video of Tsarnaev and his brother, Tamerlan, and identified them as suspects in the bombing.

But Tazhayakov’s lawyer, Matthew Myers, said his client was a naive college kid who was prosecuted because he was a “friend of the bomber.” Myers said Tazhayakov and another friend, Robel Phillipos, sat passively watching a movie in Tsarnaev’s dorm room as Kadyrbayev took the backpack.

Prosecutors acknowledged that Kadyrbayev is the one who actually threw away the items taken from Tsarnaev’s room, but they said Tazhayakov agreed with the plan.

The backpack and fireworks were later recovered in a New Bedford landfill. Prosecutors said the fireworks had been emptied of their explosive powder — an ingredient that can be used to make bombs.

Tamerlan Tsarnaev was killed in a shootout with police. Dzhokhar Tsarnaev escaped, but was found later that day, wounded and hiding in a boat parked in a backyard in nearby Watertown.

Dzhokhar Tsarnaev has pleaded not guilty in the bombing and is scheduled to stand trial in November. He faces the possibility of the death penalty if convicted.

Tazhayakov is scheduled to be sentenced on Oct. 16. He faces a five-year maximum for conspiracy and 20-year maximum for obstruction but likely will get a lot less under sentencing guidelines.

(AP)