A suspected illegal immigrant was rescued Tuesday by San Diego firefighters after becoming ensnared in the razor wire on top of a fence at the U.S.-Mexico border, Fox5SanDiego.com reported.

Border Patrol agents saw the man stuck in the fence east of Otay Mesa just before 3:45 p.m., and they called the San Diego Fire Department, the report said. It took rescuers more than an hour to free the man stuck some 20 feet above the ground. The undocumented man was evaluated by EMTs at the scene and was not injured. He was handed over to border agents and taken into custody, the report said.

The concertina wire on top of the fence is two rows deep and designed to make moving forward or backward excruciatingly painful. One strategy border crossers use to scale the fence successfully is to employ a ladder and then drape a blanket over the razor wire.

"The secondary fence is designed to slow, to impede the pedestrian traffic," Ken Hamill, a border agent, told Fox5SanDiego.com. Adding just a few minutes to the climb enables authorities to swoop in.

Reports of an individual stuck on the fence is not particularly uncommon. In the past year, 21 people have had to be rescued while attempting to cross the border, Border Patrol told the station. In October, for example, a jeep got stuck on the wall in Yuma, Ariz.

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