TRABUCO CANYON (CBS) — A team of rescue workers Friday had to help three horses who fell off a trail and into a ravine in Trabuco Canyon in the Cleveland National Forest.

Four horses fell off West Horsethief Trail this morning, and one of them died, U.S. Forest Service spokesman Brian Harris said.

The forest service was alerted about 10:45 a.m., he said.

It’s not clear how the horses tumbled into the ravine, but they apparently were part of a four-day ride from San Juan Capistrano to the Corona/Norco area, Harris said.

“We don’t have any cellphone contact there so it’s difficult to communicate,” Harris said.

The Orange County Fire Authority has lent a couple of helicopters to the search, OCFA Capt. Marc Stone said.

An animal rescue team from Norco that specializes in rescuing cows that fall into ravines also were responding, Harris said.

Rescue workers cut a path for one horse that could walk out on his own power.

Two horses had to be tranquilized and airlifted out by helicopters.

Three rescue workers also had to be airlifted out. “They weren’t injured, but they were exhausted,” said Harris.

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