Last Updated Jan 19, 2016 1:18 PM EST
LANDSTUHL, Germany -- Former U.S. Marine Amir Hekmati said Tuesday he felt humbled and lucky to be free again, two days after being released alongside three other Americans in a prisoner swap with Iran.
News of his impending release came as a surprise and was hard to believe at first, Hekmati said in his first statement following his release Sunday.
"I was at a point where I had just sort of accepted the fact that I was going to be spending 10 years in prison, so this was a surprise and I just feel truly blessed to see my government do so much for me and the other Americans," he told reporters outside the U.S. military's Landstuhl Regional Medical Center in Germany where he was taken for treatment.
There was no advance warning of his release, he added. "They just came one morning and said 'pack your things.'"
The 32-year-old says he and his fellow prisoners weren't able to relax until the Swiss government plane they were flown out in had left Iranian airspace, after which "champagne bottles were popped."
Hekmati thanked U.S. President Barack Obama, Congress and his other supporters, reserving special thanks for the U.S. Marine Corps.
Asked about his 4 1/2 -years in Iranian prison, Hekmati said it "it wasn't good," but declined to elaborate.
"He has not had much of a chance to exercise and he's lost some weight but he looks fit and I think he is on the mend," U.S. Rep. Dan Kildee, a Democrat from Hekmati's home state of Michigan, earlier told The Associated Press.
"A better diet and a chance to exercise... and I think he'll turn out to be just fine."
Hekmati, Washington Post reporter Jason Rezaian and pastor Saeed Abedini arrived late Sunday at Landstuhl for treatment. A fourth American released in exchange for the U.S. pardoning or dropping charges against seven Iranians opted to stay in Iran, and a fifth American was released separately.
Rep. Jaret Huffman, a Democrat representing Rezaian's home district in California was also visiting Landstuhl. He said there were "tears, and smiles and hugs" when the family was reunited.
"He continues to be in great spirits, his health is sound, he's going through a process and it's going to take a few more days, but Jason's on track to get his life back," Huffman said.
Kildee said he had a steak dinner Monday night with Hekmati as well as Hekmati's two sisters and brother, and that he seemed in "pretty good spirits" for someone who had been incarcerated for so long.
"We talked a bit about his experience, but I think he was just appreciating his freedom and trying to enjoy it as much as he could," Kildee said.
Hekmati was detained in August 2011 on espionage charges. He says he went to Iran to visit family and spend time with his ailing grandmother. After his arrest, family members say they were told to keep the matter quiet.
He was convicted of spying and sentenced to death in 2012. After a higher court ordered a retrial, he was sentenced in 2014 to 10 years in prison on a lesser charge.
Hekmati was born in Arizona and raised in Michigan. His family is in the Flint area. He and his family deny any wrongdoing, and say his imprisonment included physical and mental torture and long periods of solitary confinement in a tiny cell.
Kildee said he looked forward to talking more with Hekmati about his experience in the coming months but did already learn some details.
"We talked about a few of the aspects of his incarceration, (he) described the prison conditions as being bleak as we know them to be by reputation, described the fact that he had been told he was going to be released on several occasions, so even when this moment came he wasn't sure it was really true until he was at the airport," he said.
"In some ways that was another way to sort of provide psychological torture - to continue to torment him with his release."
Huffman said Rezaian had told him his captivity was "horrific" with occasional "comedic moments" but that he didn't want to go into further details.
"It's Jason's story and I think the world wants to hear directly from him," Huffman said. "But what amazed me about my time with him last night is his spirit - if the Republican Guard thought they'd break the spirit of this guy, they failed miserably."
For now, Hekmati is focused on getting home soon, though it's not yet clear when he'll be released from the hospital, Kildee said.
"He's really anxious to see his parents," Kildee said. "His father's quite ill - he was healthy when Amir went into prison and he's quite ill now - so I know that's an important part of the reunion."
Rezaian was finally reunited with his wife, mother and brother. He also met his bosses from the paper and said, "I want people to know that physically, I'm feeling good. I know people are eager to hear from me, but I want to process this for some time."