A U.S. Marine is still imprisoned in Mexico after accidentally crossing the U.S.-Mexican border on March 31.

Andrew Tahmooressi, 25, missed his last chance to make a U-turn back into the U.S. because of poor signage. He was found to be in possession of three registered weapons, including one assault rifle. He has been jailed for almost two months, and many are saying a simple phone call and better cooperation between the U.S. and Mexico could have prevented this whole ordeal.

"This should have been a phone call," said a border patrol supervisor who used to work the San Diego sector. "I would call my counterpart on the south side, call in a favor and Sgt. Tahmooressi would have been back in a few hours. Why that didn't happen here, I don't know. There's no reason Mexico City and Washington should be involved in something like this."

Due to construction, the "U-turn back to the U.S." sign at the border is now a small white sign on the ground instead of the former large green sign that was displayed before construction. Mexican military and police officers have accidentally crossed the border as well. Usually, they are questioned by the U.S. Border Patrol and sent on their way.

"We had several incidents where Mexican military or federal police or local police inadvertently crossed the border, armed, on the U.S. side and were apprehended by us," Bingel said. "We were able to usually dispense with those cases pretty quickly and get them back home once we established the intent wasn't there to do anything nefarious. I really can't explain why it has taken the Mexican government this long. If they're trying to make a point about broader issues of arms smuggling southbound, I think they've picked really the wrong case to do that with."

Customs and Border Protection spokeswoman Angelica De Cima said some travelers do miss the U-turn lane but doesn't know how many.

"He's not trying to smuggle arms southbound," said Thad Bingel, a former chief of staff at Customs and Border Protection. "He made a wrong turn. He had weapons in the car. He was arrested for that, but he's certainly been held long enough to determine his intent and to send him home to his family."

Tahmooressi had a pistol, a shotgun and an AR-15 assault weapon. Guns are illegal in Mexico, and the AR-15 weapon surely got law enforcement's attention.

Mexican officials have claimed that Tahmooressi has changed his story. They say he originally said he was going to see friends and then later said he just made a mistake.

The state department is working hard to get Tahmooressi released, and some are suggesting the U.S. should cut off some of the aid it provides to Mexico.

"I never meant to be in Mexico. ... I had no bad intentions, I had no intentions of smuggling my weapons, I had no intention of selling them or anything of the sort," Tahmooressi said.

Related