Rocks Found on Beach Mysteriously Catch Fire in Woman's Pocket

A California mother is recovering from second- and third-degree burns after colored rocks her family collected from a southern California beach unexpectedly caught fire while in her shorts pocket.

"We were talking about who was going to pick up the babysitter," Lyn Hiner said today on "Good Morning America." "And all of a sudden something hot on my leg just sort of started to bother me so I started thinking it was a bug bite, so I started slapping it and the next thing I know my pants were on fire." 

The harmless-looking, green- and orange-colored rocks, which Hiner's daughters found Saturday on San Onofre State Beach in southern California, are now the subject of an intense scientific investigation.

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