A Mexican judge has ordered Sgt. Andrew Tahmooressi back to prison after the U.S. Marine made his first full appearance in court Wednesday on charges that he broke the law when he crossed into the country earlier this year with military-grade firearms.

Mexican authorities defended their decision to move forward prosecuting him on June 6, contending not knowing their laws does not exempt him from them, Circa reported.

The news comes after a bipartisan group of U.S. lawmakers sent a letter requesting his immediate return Wednesday. Tahmooressi has now been imprisoned in Mexico for 101 days.

The 26-year-old veteran of two tours in Afghanistan, who was being treated for Post Traumatic Stress Disorder related to his combat, says he accidentally crossed a California border checkpoint late March 31 and could not turn around before reaching the Mexican government checkpoint. Tahmooressi was in San Diego for treatment related to his PTSD and had all his possessions in his car, after previously moving from Florida. Despite declaring his three-registered weapons to agents at the border, Mexican authorities charged him with violating their gun laws.

On Wednesday, he made his first official courtroom in front of a judge. It was not immediately clear what he said during the private hearing, but his lawyer Fernando Benitez said he was confident things were headed in the right direction, despite the judge’s order to keep him imprisoned, Fox News reported.

Andrew Tahmooressi has been held by Mexican authorities since March 31. (Photo via WSVN-TV)

Andrew Tahmooressi has been held by Mexican authorities since March 31. (Photo via WSVN-TV)

Following the hearing, Tahmooressi was escorted by heavily-armed guards back to El Hongo Prison in Tecate, according to Fox News.

Earlier, Jill Tahmooressi, Andrew’s mother, told TheBlaze she was praying that “God will grant us a miracle today.”

“I’m still hoping and praying for a miracle,” she added, holding back her tears. “It was a wrong turn that he’s been put in this situation and as much as we’re staying hopeful, we also have to be realistic. However, God is mighty and let’s hope there is a direct line to this judge’s heart.”

The letter sent by Rep. Duncan Hunter (R-Calif.) had offered her hope, she told TheBlaze. The letter stated that lawmakers believe the 26-year-old veteran accidentally crossed the border as he claims. It cites a last-ditch 911 call made by the Marine as evidence.

“One of the most compelling pieces of evidence is a 911 call Andrew made at the border checkpoint, where he stated that he was unaware of his location,” the letter said. “It’s also important to take into account that Andrew was new to the San Diego area, without permanent housing, and had many of his possessions in his car. Like many of those new to the area, he was unfamiliar with the often confusing roads along the border and was unable to turn around before entering Mexico.”

Jill Tahmooressi said she also received a letter Monday from U.S. Ambassador to Mexico Anthony Wayne, saying “he was monitoring the situation and that the local consulate has been supporting Andrew.”

This story has been updated.

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