WASHINGTON (AP) — The Army says it will stop injecting monkeys at Aberdeen Proving Ground with a nerve-blocking drug meant to simulate a nerve-gas attack.

The Washington Post reports that the decision follows sustained pressure from animal-rights groups and Maryland Republican Rep. Roscoe Bartlett.

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An Army spokesman told the Post on Thursday that the Army Medical Research Institute of Chemical Defenses at Aberdeen will phase out the nerve tests on the primates.

Bartlett told the newspaper that two generals indicated to him the testing would end by year’s end.

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The Physicians Committee for Responsible Medicine petitioned the Defense Department to end the allegedly inhumane tests.

An expert at the Center for Biosecurity at the University of Pittsburgh Medical Center says patient simulators can provide better training than live monkeys.

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