(CNN) - Thousands of people have signed a White House petition demanding the release of a U.S. Marine jailed in Mexico.
Nick Valencia talked to the marine firsthand and has more on what's happening with the case.
Days before Andrew Tahmooressi was arrested, he was living at a friend's house in San Diego, looking for emotional support after two combat tours in Afghanistan.
"We noticed the problems face to face where he was just acting distant. And we could tell that it was just a clear sign of PTSD," said Sam Vranicar, who served with Tahmooressi in Afghanistan.
But over the course of the month, his friends told CNN things started to look up until the night of March 31, he parked his car on the U.S. side, and walked into Mexico to patronize an establishment popular with marines, according to his mother.
He eventually returned to the U.S. on foot, got in his car, and then made a fateful turn into Mexico.
He made a left out of a lot completely missing the sign that says Mexico only, no U.S.A. return, and got onto that on-ramp, straight into Mexico.
"I crossed the border by accident and have three guns in my truck and they're trying to possess, they're trying to take my guns from me," Tahmooressi said.
Not every car that goes into Mexico gets checked.
The director of the Tijuana checkpoint told Mexican media, Tahmooressi was pulled over because he didn't have a front license plate.
Never once did he say he was a U.S. Marine, Mexican officials said, or that he got lost.
He's been imprisoned in Mexico ever since.
He was spoken to on the phone from the Mexican prison where he's being held.
Valencia: What have things been like for you there in Mexico, Andrew?
Tahmooressi: Not very good in the beginning. For like the first month, things were not that, not that good at all.
Tahmooressi is imprisoned in Tecate, Mexico. When he was spoken to by phone, he said he was being mistreated by prison officials, abused, not given enough food or water.
We weren't able to get inside to see for ourselves, but when I spoke to the head of police at the prison, he denied those allegations and said the Marine is being treated well.
But the drama surrounding his case has caused court delays.
After firing his attorney before the first proceedings, Tahmooressi may have to wait weeks to get another hearing.
He's willing to wait, he says, optimistic that he will be released soon.
Valencia: What gives you that confidence, Andrew?
Tahmooressi: That I'm not guilty and I'm confident that the judge is going to realize that I'm not a guilty man.
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