Boston Marathon bomber's friends plead not guilty to obstruction

Two college friends of the surviving Boston Marathon bombing suspect pleaded not guilty Tuesday to allegations they conspired to obstruct justice by agreeing to destroy and conceal some of their friend's belongings as he evaded authorities.

Dias Kadyrbayev and Azamat Tazhayakov, both nationals of Kazakhstan who shared an apartment in New Bedford, Mass., became friends with bombing suspect Dzhokhar Tsarnaev when they all started school at University of Massachusetts-Dartmouth in 2011.

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Tsarnaev is accused of setting off two bombs near the race's finish line that killed three and wounded hundreds April 15. He has pleaded not guilty. Authorities say he was working with his older brother, who died during the manhunt for the suspects days later.

On April 18, Tsarnaev's friends took his laptop from his dorm room, along with a backpack that had fireworks with explosive powder and a jar of petroleum jelly, federal authorities alleged in an indictment last week.

They say Kadyrbayev had gotten a text from Tsarnaev suggesting that he could go to his dorm room and "take what's there." The indictment also alleged that Kadyrbayev later put the backpack with the fireworks and jelly in a trash bin outside the New Bedford apartment after Tazhayakov agreed.

It also said Kadyrbayev told Tazhayakov he believed Tsarnaev had used the jelly "to make bombs."

The indictment also alleged that the next morning, as Tsarnaev was identified in news reports as a bombing suspect, the two saw a garbage truck empty the bin.

Kadyrbayev's attorney has said his client never knowingly took evidence from the dorm room and fully co-operated with the FBI. The attorney said his client also was part of voluntarily turning over Tsarnaev's laptop and telling the FBI where to find the backpack.

Tazhayakov's lawyer has said his client never agreed to anything when it came to disposal of the backpack with the fireworks. He said his client hasn't done wrong and he's been trying to get authorities to drop the case.

Both defendants face up to 25 years in prison on charges of obstruction of justice and conspiracy to obstruct justice. Family members of both attended the hearing.