(CNN)Kayla Mueller was difficult to reach -- 6,000 miles away and held captive by the Islamic militants of ISIS. But her family and U.S. government officials say they went to great lengths to try to rescue the 26-year-old humanitarian worker, efforts that ultimately failed. Her parents announced Tuesday they'd received confirmation she had died. Now they're working to bring her body back from Syria. U.S. troops may have come close to rescuing Mueller in July when they staged a daring raid at an abandoned oil refinery near Raqqa in Syria in an attempt to find journalist James Foley, who was executed by ISIS in August, and other hostages.
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U.S. troops made a rescue effort in July but didn't find Mueller or other hostages
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Mueller's parents asked the White House about swapping a prisoner for their daughter
Gosar said government sources told him a man showed up at a terrorist training camp in @placeholder claiming to be Mueller's husband.