A small boat believed to be carrying migrants capsized early Monday off the coast of San Diego, leaving at least three people dead and four others injured. The U.S. Coast Guard said Monday afternoon that crews were searching for at least seven others after earlier saying nine people were missing.
The panga-style boat — a small, open, outboard-powered fishing vessel — overturned near Torrey Pines State Beach with at least 16 people on board, a U.S. Coast Guard official told CBS News. Among them were at least two children, according to San Diego CBS affiliate KFMB, which also reported that four people were hospitalized in the aftermath of the incident.
The Coast Guard official told CBS News that it is treating it as a suspected human smuggling incident.
U.S. Coast Guard Petty Officer Chris Sappey told The Associated Press that it was unclear where the boat was coming from before it flipped about 35 miles north of the Mexico border. He said similar vessels were commonly used by smugglers.
"They were not tourists," Sappey said. "They are believed to be migrants."
Officials had no other details about those on board, including the three people who died. It was also unclear if anyone made it to shore on their own and left the area, The AP reported.
The San Diego County Sheriff's Office said its deputies were assisting.
The sheriff told KFMB that no one had been detained in connection with the incident.

Video published by the station showed the empty boat near the shoreline at Torrey Pines State Beach, while lifeguards patrolled the water and law enforcement vehicles parked on the sand. A Coast Guard helicopter surveyed the area from above.
Witnesses reported seeing a boat capsize near the shore at about 6:30 a.m. local time, Lt. Nick Backouris of the San Diego Sheriff's Department told The Associated Press.
"A doctor hiking nearby called in and said, 'I see people doing CPR on the beach, I'm running that way,'" Backouris said.
The wooden boat was more than 20 feet long, and had scuffed blue paint and wooden planks for seats, The AP reported. Inside the boat were a pair of running shoes, more than a dozen life vests, an empty waterproof cellphone bag and various water bottles.
In addition to sheriff's deputies and Coast Guard, officials with the Encinitas Fire Department and U.S. Customs and Border Patrol were also at the scene, KFMB reported.
The immigration status of those on board was "not known at the moment," Jorge Sanchez, the deputy fire chief, said during an interview at the scene. Sanchez said multiple people were found on the beach after the boat overturned, and confirmed it was considered a "mass casualty incident."
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Emily Mae Czachor