BOSTON (AP) — Appeals lawyers for convicted Boston Marathon bomber Dzhokhar Tsarnaev are asking authorities for the recordings of interviews with a suspect in a triple-homicide in Massachusetts who was shot in 2013 during a confrontation with an FBI agent.

The attorneys, whose argument for sparing Tsarnaev’s life is due next month before the 1st U.S. Court of Appeals, filed the motion for the recordings of Ibragim Todashev on Tuesday without spelling out their reasons for asking.

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Todashev knew Dzhokhar Tsarnaev’s older brother, Tamerlan. He allegedly told police about a month after the marathon bombing that he and Tamerlan Tsarnaev had killed three men in Waltham in 2011.

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Todashev was fatally shot by an FBI agent in Orlando, Florida, after allegedly charging at the agent with a metal broomstick.

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