A 28-year-old El Toro Marine sergeant, running 3 miles as part of a semiannual physical fitness test, collapsed and died of a heart attack Wednesday at the Marine helicopter base in Tustin.
The Marine, identified as Joseph Serna of Moreno Valley, Calif., collapsed on the outdoor track at the Tustin base within view of an audience attending a ceremony for officers completing a training course, according to one witness. An autopsy showed Serna died of a coronary occlusion, coroner's investigators said.
Serna, a mechanic originally from Fullerton, was taken by helicopter to Western Medical Center in Santa Ana, where he was pronounced dead at 9:11 a.m., according to a Marine Corps spokeswoman. He is survived by his wife and two daughters.