The family of an American psychotherapist detained in Syria says the US government

has informed them that he died in custody.

Madjkamalmaas was one of half a dozen Americans believed held by Bashar al-Assad's regime.

And as Nick Schifren reports, some of them were allegedly tortured,

some even murdered.

Nick.

When Mad Klamaz wasn't hiking up a mountain or fishing in the ocean, he was with his brood of

grandchildren. When he wasn't with them, he was helping other people's children who'd

suffered trauma in conflict or natural disasters. He led an NGO that treated young victims of the war in Bosnia, the tsunami in Indonesia, and Hurricane Katrina.

In 2017, he traveled to Damascus to pay respects after his father-in-law's death. He never came home.

Last week the U.S. government told the Kamalma's family that he was likely killed, a prisoner of Syria.

I'm now joined by two of Madh Kamal-Mazin's daughters, Ula and Mariam.

Ula, can you tell me about your father?

He was a kind-hearted loving empathetic individual who lived his attributes to his various wolves as a family man and

a psychotherapist who was devoted to his work and his family.

Mariam, what did the US government tell you

about what happened?

So there was around eight US government officials that had gathered for our meeting to discuss my father's fate.

And they very clearly stated that they believe they have highly classified information that indicates that he has passed.

This piece of information was highly credible and they truly believed

that he was deceased within the Syrian government's hands, within the prisons of the Syrian government.

There was no way for us to continue having any form of hope, basically, that he would

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