WORCESTER, Mass. — A magistrate judge on Monday agreed to release a friend of Boston Marathon bombing suspect Dzhokhar Tsarnaev from federal custody while he awaits trial for allegedly lying to federal investigators probing the bombings.

Robel Phillipos, 19, was charged last week with lying to investigators about visiting Tsarnaev’s college dorm room after the bombings. The University of Massachusetts Dartmouth student faces a maximum of eight years in prison if convicted.

Prosecutors initially asked that Phillipos be held while he awaits trial, arguing that he poses a serious flight risk. But both sides said in the court motion filed Monday they agreed that Phillipos should be released on $100,000 bond, be confined to home and wear an electronic monitoring bracelet.

Assistant U.S Attorney John Capin said documents filed by Phillipos’ defense attorneys, including many affidavits showing support from family and friends, might be viewed as indirectly questioning the government’s case against Phillipos.

“The government stands by its allegations,” Capin said.

Magistrate Judge Marianne Bowler agreed to the strict house arrest during a hearing Monday afternoon. She told Phillipos he was allowed to leave the house only for meetings with his lawyers or true emergencies.

A huge crowd of supports, including Phillipos’ relatives, friends and grade-school principal, showed up to the courthouse for the detention hearing. It was not immediately clear when Phillipos would be released.