COACHELLA, Calif. (AP) - Two men were found dead in a horse trailer at a Southern California equestrian park after they were apparently overcome by carbon monoxide fumes from a gas generator, authorities said.

The men, identified as Jorge Rodriguez-Ramirez, 47, of Vancouver, Wash., and Armando Sanchez Gallardo, 21, were discovered early Friday, Riverside County sheriff's officials said. It wasn't immediately known where Gallardo was from.

Their bodies were in a trailer parked in a lot at the HITS Desert Horse Park in Thermal, located a few miles south of Coachella in Riverside County. A portable gas generator had been used to keep them warm as they slept.

"The decedents appeared to have been overcome by carbon monoxide fumes from the generator's exhaust," the sheriff's department said in a statement.

Autopsies were expected to be performed Monday.

Further details were not immediately available.