BOSTON (AP) — 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.

Wearing shackles and orange jail jumpsuits, both defendants looked happy to see family across the courtroom before emphatically entering their pleas.

Dias Kadyrbayev and Azamat Tazhayakov, both 19-year-old 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.

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."

Kadyrbayev's attorney Robert Stahl has said his client never knowingly took evidence from the dorm room and cooperated with the FBI.

Tazhayakov's lawyer Arkady Bukh has said his client never agreed to anything when it came to disposal of the backpack with the fireworks.

Both face up to 25 years in prison.

Tazhayakov's father said afterward that his son is "absolutely not guilty" and that the FBI made a mistake by arresting him.

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