Four U.S. Marines, first believed to be trapped in an East County cave, managed to free themselves before morning.
Two men and two women found themselves stuck in the Thunder Canyon caves of Pine Valley late Monday.
The group had been hiking and repelling when they found they could not climb out of a cave they had just reached.
Sheriff's deputies received a call from the hikers at about 8:30 p.m. Monday that they were trapped in the drop-in cave, deputies said.
Due to the power lines in the area, emergency personnel could not dispatch a helicopter to pull them out.
The San Diego County Sheriff’s Department Search and Rescue team started preparing for a rescue along with the San Bernardino cave rescue. The teams decided to drop blankets, water and Gatorade to the hikers while they wait for rescue.
However, when the supplies were delivered, the Marines had managed to find a way out of the cave and freed themselves.
Despite earlier reports that one of the hikers had an injured shoulder, deputies said there were no injuries in the incident.
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