SAN CLEMENTE – A 43-year-old woman is undergoing surgery after two rocks that she collected at a South County beach ignited in the pocket of her shorts, officials from Orange County Fire Authority said.

The incident happened about 3:30 p.m. Saturday when the woman was standing in her kitchen after returning from an outing to Trestles Beach. She had been home for about an hour when the pocket of her cargo shorts caught fire, OCFA Capt. Marc Stone said.

The woman tried to stop, drop and roll but was unsuccessful in getting the flames out, Stone said.

Her husband also tried to help and got second-degree burns when he tried to pull the shorts off, Stone said. The rocks, described as small, the size of a hamburger patty, smooth and orange and green in color, fell from the shorts onto the floor and continued to burn the wood floor and fill the house with smoke.

Firefighters responded immediately to the home on Avenida Estrella. When they arrived, the husband had successfully gotten the shorts off his wife and was hosing her down on the front deck with a garden hose, Stone said.

Paramedics treated the woman for severe second- and third-degree burns on her right leg from her thigh to her knee and on her right arm, Stone said. The husband also was treated for second-degree burns on his arm.

Both were taken to Western Medical Center in Santa Ana. Firefighters took the rocks with them to show to doctors, Stone said.

“I talked to the paramedic who treated her, and in his 27 years in responding to calls near the beach, he’s never seen this,” Stone said. “The rocks were still smoking when firefighters took them to the hospital.”

OCFA hazardous materials unit was consulted. The rocks have been taken to Orange County Public Heath and are undergoing testing to see what happened, Stone said. “Tests are expected to take a few weeks because they are dealing with an unknown.

“There is phosphorous that naturally occurs on the sand at the beach, but no one has ever heard of pants catching fire,” Stone said.

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