A man surfing in the waters of San Francisco's Ocean Beach died Sunday night, following calls to 911 reporting a surfer in need of rescue.

According to San Francisco Fire Department spokesperson Jonathan Baxter, SFFD and National Parks Service units were called to the Ocean Beach shoreline near Rivera Street at 6:30 p.m. Sunday.

A 29-year-old man was pulled from the waters, Baxter says. Though crews performed CPR on the man, since identified by the San Francisco Medical Examiner's office as SF resident Jason Zumbo, he was pronounced dead.

Bay City News reports quotes Baxter as saying that "it is unclear if Zumbo experienced a medical event in the water," but one rescuer who spoke with SFist on the condition of anonymity claims that it was a "pretty straightforward drowning." When contacted by SFist, the San Francisco Medical Examiner's office declined to confirm Zumbo's cause of death.

Following the April death of two wading teens, the safety of Ocean Beach has come under renewed scrutiny. That month, Supervisor Eric Mar called for lifeguards on the beach, as well as improvements to existing signage outlining the hazards at that stretch of shoreline. As effort to reach Mar for comment on Sunday's death was not successful as of publication time.

Previously: 'Education,' Lifeguards Proposed For Ocean Beach As Yet Another Distressed Swimmer Is Rescued