Over the past few weeks, Greta Van Susteren has highlighted the plight of a former U.S. Marine who has been held in an Iranian prison for more than three years.

Sgt. Amir Hekmati, an Iranian-American with dual citizenship, was arrested while on a trip to Iran to see his ailing grandmother and accused of being an American spy, convicted on a lesser charge and sentenced to 10 years in prison.

His family says he has been tortured by Iranian authorities.

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Rep. Dan Kildee (D-Mich.) told Van Susteren tonight about his efforts in trying to get Hekmati to be released. Kildee explained that he is pushing a bipartisan resolution that demands the release of the American individuals being held in Iran. 

"This is a very simple, very straightforward, standalone resolution that says 'Iran must release the Americans that they hold,'" Kildee said. "It's clearly a signal to Iran that if they want to be taken seriously, they can't hold political prisoners."

He added that "it's also important that the American people, through their Congress, speak, and that everybody involved in this...understands this has to be a very high priority."

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Van Susteren also talked with Amir Hekmati’s sister, Sarah Hekmati, his brother-in-law, Dr. Ramy Kurdi, and Montel Williams, who has spoken out forcefully in support of the former Marine.

"It's never going to be enough until Amir comes home," Sarah Hekmati shared. 

Kurdi added that "it's time for Amir to come home."

Watch the full video above.