Update, 3:10 p.m.: Napa County Sheriff divers have found the body of a drowning victim this afternoon in Lake Berryessa, and identified him as 24-year-old Kevin Yip of San Francisco, according to Public Information Officer Tracey Stuart.
"They found him at 12:05 p.m. near where here was last seen in 50 feet of water with zero visibility," Stuart said. "...He went for a swim and began to struggle."
Stuart said an autopsy should be conducted sometime this week.
By Bay City News Service
Divers from the Napa County Sheriff's Office this morning were searching for a 24-year-old man who is believed to have drowned in Lake Berryessa on Sunday afternoon, a sheriff's captain said.
The man, possibly a San Francisco resident, went swimming without a flotation device off a pontoon boat in the Portuguese Canyon area in the southern part of the lake in Napa County, Capt. Tracey Stuart said.
Other people on the boat saw him struggling before he went under water, but were unable to help, Stuart said.
A person in the Pleasure Cove area of the lake heard screaming and called the sheriff's office around 3:10 p.m., Stuart said.
Dive teams were at the lake at 9 a.m. today, Stuart said.
Also on Sunday, a 6-month-old child was taken to a hospital after a boat capsized around 4:40 p.m., Stuart said.
The baby was trapped under the boat, Stuart said. No other information was available about that incident.