Heartbreaking 'Proof of Life' Video of ISIS Hostage Kayla Mueller Emerges: 'It's Very Terrifying Here'

The video had not been seen publicly, until now.

A 2013 video of American hostage Kayla Mueller made by her ISIS captors has been released publicly for the first time by her parents.

Mueller, 25, was kidnapped in Syria three years ago as she left a Doctors Without Borders camp. The Arizona native had been an aid worker in the war-ravaged region.

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Carl and Marsha Mueller shared the 10-second tape with ABC News.

The woman had been missing from the Syrian city of Aleppo for nearly a month when ISIS terrorists emailed the clip, designed to prove their daughter was still alive.

“My name is Kayla Mueller,” she says, looking drastically thinner with her head covered by a scarf. “I need your help. I’ve been here too long, and I’ve been very sick. It’s, it’s very terrifying here,” she says before the video abruptly ends.

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Her parents told the network they were destroyed by her abduction.

"You just go into almost a catatonic state," her dad said, describing his reaction to first seeing the footage. "You can’t even stand up."

Her mother added: "I saw how thin she looked, but I saw that her eyes were very clear and steady," said Marsha Mueller. “It broke my heart, but I also saw her strength."

Kayla was killed in a Jordanian air strike last year, according to statements released by ISIS. Her parents have criticized President Obama over his administration’s handling of her abduction.

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