Russian relatives of Boston Marathon bomber Dzhokhar Tsarnaev are expected to testify at his trial as his lawyers continue to make their case to spare his life.
Five family members are expected to take the witness stand Monday in federal court.
Prosecutors urged Judge George O'Toole Jr. last week to press Tsarnaev's lawyers to make sure his relatives testify soon because 16 FBI agents have been assigned to guard and protect them while they are in the United States. The family members arrived in Boston on April 23.
"It's an enormous expense and distraction for the agency, and that's just part of the expense that the government has endured," Assistant U.S. Attorney William Weinreb said during a sidebar discussion in court with Tsarnaev's lawyers and the judge, according to a transcript that was made public.
Three people were killed and more than 260 were injured when two pressure-cooker bombs exploded near the marathon finish line April 15, 2013.
Tsarnaev was convicted last month of 30 federal charges in the bombings, including 17 that carry the possibility of the death penalty. Now 21, he moved to the U.S. with his family in 2002.
His Russian relatives were expected to testify Thursday, but the trial was suspended that day because a juror became ill.
Neither prosecutors nor Tsarnaev's lawyers would reveal the identities of the relatives.
Prosecutors say Tsarnaev was an equal partner in the bombings with his radicalized older brother, Tamerlan, and have urged the jury to sentence him to death.
Tsarnaev's lawyers say Tamerlan was the mastermind of the attack and lured his brother into his plan.