Republican lawmakers allege in a letter to Attorney General Eric Holder that a key figure in the failed Fast and Furious anti-gunrunning operation has been allowed to earn a second paycheck while still receiving his government salary.

The new allegations come as Holder reviews the long-awaited internal report detailing what happened in — and who is to blame for — Fast and Furious, in which the U.S. knowingly let some 2,500 weapons slip into the hands of the Sinaloa Cartel in Mexico, failing to track the guns as planned.