BOSTON (AP) — Attorneys for Boston Marathon bombing suspect Dzokhar Tsarnaev are formally asking a federal judge for more time to prepare arguments that their client shouldn't be subject to the death penalty.

In a brief filed Friday with the U.S. District Court in Boston, Tsarnaev's lawyers say the current Oct. 24 deadline doesn't allow for a "reasonable opportunity" to make their case.

Twin bombings at the April 15 marathon killed three people and injured more than 260.

Federal prosecutors have said they plan to make a recommendation about whether to pursue the death penalty to U.S. Attorney General Eric Holder by the end of the month. Holder will make the final decision.

Prosecutors said at a recent hearing that they believe the defense has had ample time to respond.

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