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By Daniel Lovering
BOSTON, Aug 21 (Reuters) - A friend of accused Boston Marathon bomber Dzhokhar Tsarnaev pleaded guilty on Thursday to charges of hindering the investigation into the blasts in a deal with prosecutors that calls for a prison sentence of up to seven years.
Dias Kadyrbayev, a 20-year-old Kazakh national, had been scheduled to go on trial next month and was facing up to 25 years in prison on charges of conspiracy and obstruction of justice for removing a backpack and other evidence from Tsarnaev's dormitory room in the days after the bombing.
Three people were killed and more than 260 were injured when two pressure-cooker bombs exploded near the finish line of the Boston Marathon on April 15, 2013.
Kadyrbayev also agreed to be deported from the United States as part of the agreement. U.S. District Judge Douglas Woodlock said he would not accept the deal immediately but scheduled a sentencing hearing for Nov. 18.
Prosecutors had argued that Kadyrbayev and two other friends of Tsarnaev impeded the investigation by removing evidence including a backpack containing empty fireworks casings, a jar of Vaseline, a thumb drive and a laptop computer from Tsarnaev's dorm room at the University of Massachusetts at Dartmouth.
On Thursday, Kadyrbayev changed his plea to guilty on both the conspiracy and obstruction charges during an appearance at federal court in Boston. He wore a blue polo shirt and sneakers, and his father sat in the courtroom behind him.
His attorney, Robert Stahl, said afterward that Kadyrbayev had "accepted full responsibility for his actions" and was unaware that Tsarnaev or his brother Tamerlan allegedly had been planning the attack.
"Dias is a young man, he was barely 19 when this happened and he made a terrible choice, an error in judgment that he is paying for dearly," Stahl told reporters outside the courthouse.
SECOND FRIEND CONVICTED
A second friend of Tsarnaev, Azamat Tazhayakov, was convicted of the same charges last month after six days of testimony by federal agents and other witnesses, though the jury found him not guilty of charges related to the laptop computer.
Tazhayakov, who shared an apartment with Kadyrbayev, faces up to 20 years in prison on the obstruction of justice count and up to five years on the conspiracy count. He is scheduled to be sentenced on Oct. 16.
A third man, Robel Phillipos of Cambridge, Massachusetts, faces a less serious charge of lying to investigators, which carries a possible 16-year sentence. None of the three men has been accused of playing any role in the bombing.
Kadyrbayev and Tazhayakov, both Kazakh exchange students, were first questioned by investigators four days after the bombing, when heavily armed law enforcement agents arrived at their New Bedford, Massachusetts, apartment.
They were arrested the next day on charges of violating the terms of their student visas.
Before Tazhayakov's trial earlier this year, James Wiroll, a special agent with the U.S. Department of Homeland Security, testified that Kadyrbayev had told him he had thrown away the backpack and laptop after coming to suspect that Tsarnaev committed the bombing.
Tazhayakov's attorneys maintained that their client never touched the backpack or the laptop, and that it was Kadyrbayev who had handled them and later dropped the backpack into a dumpster. Agents later recovered the backpack from a landfill.
Kadyrbayev's plea agreement said the two agreed to remove the backpack and other items from Tsarnaev's dorm room and bring them back to their apartment in New Bedford.
Tsarnaev was captured following a massive manhunt in the days after the Boston Marathon bombing and is awaiting trial in November on terrorism charges. His older brother Tamerlan, also a suspect in the bombing, was killed following a shoot-out with police. (Reporting by Daniel Lovering; Editing by Frank McGurty, Peter Cooney and Eric Beech)