U.S. lawmakers sent an urgent letter to the Mexican attorney general Thursday calling for the swift release from prison of a U.S. Marine who says he accidentally crossed a border checkpoint with weapons in his vehicle, warning that Mexican military and law enforcement personnel have themselves crossed many times into the United States with weapons in tow and had exceptions made.

This May 3, 2014, photo shows Sgt. Andrew Tahmooressi left, who is being held at Tijuana's La Mesa Penitentiary. The 25-year-old Marine Corps combat veteran is being held on weapons charges for mistakenly crossing the border with a shotgun, handgun and rifle in his vehicle. If Tahmooressi is convicted, he faces six to 21 years in a Mexican prison, his lawyers said, adding that alternatively the case could be dropped if the Mexican Attorney General’s Office in Mexico City requests dismissal. SAN DIEGO, ALEJANDRO TAMAYO — AP Photo

This May 3, 2014, photo shows Sgt. Andrew Tahmooressi left, who is being held at Tijuana’s La Mesa Penitentiary. The 25-year-old Marine Corps combat veteran is being held on weapons charges for mistakenly crossing the border with a shotgun, handgun and rifle in his vehicle. If Tahmooressi is convicted, he faces six to 21 years in a Mexican prison, his lawyers said, adding that alternatively the case could be dropped if the Mexican Attorney General’s Office in Mexico City requests dismissal. (AP/Alejandro Tamayo)

Rep. Duncan Hunter (R-Calif.) sent the letter, which was signed by 21 members of Congress from both parties, regarding the imprisonment of decorated Marine Corps veteran Andrew Tahmooressi, who was taken into custody in Mexico after he inadvertently crossed the San Ysidro inspection station along the U.S.-Mexico border April 1. Andrew’s mother, Jill Tahmooressi, told TheBlaze that once her son realized he was in the wrong lane, it was too late for him to turn around. He admitted to Mexican officials that he had weapons in the vehicle, but was still taken into Mexican federal custody.

Hunter said Mexican Attorney General Jesus Murillo Karam “is in a position to deal with Andrew’s case and ensure its quick resolution.”

“Perhaps Mexico should be reminded of the hundreds of military and law enforcement incursions at the border, where officials and personnel have entered the U.S. without permission and most always carrying weapons,” Hunter said. “These incidents must be stopped altogether, but Mexico’s actions in Andrew’s case, similar to others, underscore the immediate need for a new form of legal treatment by U.S. officials when incursions occur.”

According to documents obtained by this reporter and interviews with federal law enforcement agencies, Mexican military and law enforcement officials have crossed the U.S.-Mexico border illegally with weapons hundreds of times.

The letter urges the Mexican attorney general to expedite Tahmooressi’s proceedings ahead of his next hearing on May 28 and to initiate a dismissal of charges.

“We fully respect Mexico’s right to enforce it’s laws, but we believe Andrew is not a criminal or weapons trafficker. He is a Marine Corps veteran who served his country honorably, and simply got lost in an area he is unfamiliar with,” the letter states.

Tahmooressi, who served in one of Afghanistan’s deadliest provinces, is being held at La Mesa Penitentiary, in Tijuana. The 25 year-old Marine was threatened on his first night when he was placed among the general population, Jill Tahmooressi told TheBlaze.

His mother hopes people all across the country will contact the Mexican government and sign a petition on the White House website for her son’s release.

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