RANCHO SANTA MARGARITA (CBSLA.com) — A 49-year-old Orange County firefighter suffered an apparent heart attack Monday at a station in Rancho Santa Margarita and later died.

Engineer Greg Hennessey was discovered unconscious at Orange County Fire Authority Station 45 about 9:40 a.m.

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OCFA spokesman Steve Concialdi said the 24-year veteran could not be revived.

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Hennessey was pronounced dead at Mission Hospital.

“He was well-liked, a valued member of our fire department…in the last eight years, he was a fire Explorer advisor in both Mission Viejo and Rancho Santa Margarita, where he had great joy in training teenagers and young adults,” Concialdi said.

Hennessey is survived by his mother, wife, and his 22-year-old and 19-year-old sons.

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