ANTIOCH -- A 52-year-old Oakland man who was fishing with friends for Father's Day waded into the water to untangle a line, slipped on a rock, hit his head and drowned near the Antioch Marina on Sunday, police said.

The man's name was not released.

The drowning happened at 10:15 a.m. Sunday in the area of the Dow Wetlands Preserve, said Antioch police Lt. John Vanderklugt.

It wasn't clear if the other men, who were from an Oakland church group, did not immediately see him fall or did not make it out into the water in time to save him. They attempted CPR, but the man was pronounced dead at the scene, police said. Police called it an unfortunate accident that happened quickly.

No one else was injured, and foul play is not suspected.

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