Barr said in her resignation letter the allegations are "unfounded" and are "designed to destroy my reputation," the Los Angeles Times reported.
Barr, a lawyer, joined ICE in 2009 after serving as director of legislative affairs for Homeland Security Secretary Janet Napolitano when she was Arizona's governor.
Barr was named in a sexual discrimination and retaliation lawsuit filed in May by a senior ICE agent, the newspaper said, and other agency employees later raised allegations of inappropriate behavior.
Barr, who had been on a leave of absence, said she is "confident that my reputation will be restored."
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