SAN FRANCISCO (BCN) – A man collapsed and died just before crossing the finish line of a half marathon in San Francisco’s Golden Gate Park Sunday morning, a fire dispatcher said.

Peter Hass, a 36-year-old Orinda resident, was pronounced dead near 47th Avenue and John F. Kennedy Drive at about 10:15 a.m., after collapsing while running toward the 13.1-mile mark of the Kaiser Permanente San Francisco Half Marathon, according to the San Francisco medical examiner’s office.

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The cause of death remains unknown, pending an autopsy by the medical examiner.

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Fellow runners performed CPR on Hass as they waited for emergency personnel to arrive, which didn’t happen for some 20 minutes, according to witnesses.

The 8 a.m. race had about 10,000 participants and wound from the east end of the park, by the San Francisco Zoo and ended near 47th Avenue, according to the race website.

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