SAN FRANCISCO (CBS SF) — Police in San Francisco are investigating how a man died after he was found early Friday morning unresponsive near a lively intersection in the city’s Castro neighborhood.

At 12:52 a.m., officers responded to a report of a person down on the ground near the corner of 18th and Castro streets, police said.

Officers found the man and called for assistance. Medical personnel arrived and pronounced him dead at the scene, according to police.

The investigation is ongoing, police said. The medical examiner’s office is investigating.

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