By Daniel Wallis
(Reuters) - The family of Kayla Mueller, the U.S. aid worker who died while a captive of Islamic State militants in Syria, said a prisoner swap deal cut by Washington to get back a U.S. Army Sergeant held by the Taliban hurt efforts to free her.
Carl Mueller, Kayla's father, told NBC in an interview broadcast on Monday that the family had hoped to raise money for a $6.2 million ransom demanded by his daughter's captors, even though it was a daunting amount for them to contemplate.
But relatives said Mueller's value to her jailers increased after the White House agreed last year to exchange five Taliban militants held at Guantanamo Bay, Cuba, for U.S. Army Sergeant Bowe Bergdahl, who spent five years in captivity after leaving his post in Afghanistan in 2009.
"That made the whole situation worse, because that's when the demands got greater. They got larger," Mueller's brother Eric told NBC. "They realized that they had something. They realized that, 'Well, if they're going to let five people go for one person, why won't they do this? Or why won't they do that?'"
U.S. officials said this month that 26-year-old Mueller, from Prescott, Arizona, died under unclear circumstances about 18 months after she was kidnapped while leaving a hospital in northern Syria.
White House spokesman Josh Earnest said everyone sympathized with the family and that President Barack Obama ordered a military raid to try to rescue Mueller. But the United States does not negotiate with militants such as her captors, he said.
"The president is confident his administration did do everything that was possible within the confines of that policy, using our military might, using our intelligence capability, using our diplomatic influence, to try to secure the safe release and return of Kayla Mueller," Earnest told reporters.
U.S. officials said on Feb. 10 that U.S. intelligence analysts verified Mueller's death by authenticating a message sent to her parents by Islamic State.
The militant group had said earlier she was killed in bombing by Jordanian jets near Raqqa, Syria. Jordan and U.S. officials have questioned that account.
Carl Mueller said the family really felt it had a chance, albeit slim, to get her home.
"We were in communications with them, unlike the other families," he told NBC. "But how do you raise $6.2 million? It pretty much made it impossible. We feel they really did want to release Kayla."
(Reporting by Daniel Wallis in Denver; Additional reporting by Emily Stephenson in Washington; Editing by Cynthia Johnston and Peter Cooney)