Ten people have been shot, four of them fatally, at a party in the Californian city of Fresno after the suspects snuck into a backyard filled with people and fired into the crowd.
The shooting took place about 6 pm on Sunday on the city's southeast side where people were gathered to watch a football game, police said.
Deputy Chief Michael Reid told the Fresno Bee and the KSEE/KGPE TV stations that a total of 10 people were shot, with three found dead in the backyard. A fourth victim later died in hospital.
Six others are expected to survive and are recovering in care. All the victims were Asian men ranging in age from 25 to 35.
"What we do know is that this was a gathering, a family and friend gathering in the backyard," Lieutenant Bill Dooley said.
"Everyone was watching football this evening when unknown suspects approached the residence, snuck into the backyard and opened fire."
The victims were taken to Community Regional Medical Center in critical condition with some now critical but stable, the TV stations reported.
About 35 people were at the party when the shooting began, Reid said.
"Thank God that no kids were hurt," he said.
No suspect is in custody. Police said there was no immediate indication the victims knew the shooter or shooters.
Police were going door-to-door in search of surveillance video that might help them track down the suspects. The shooting took place less than a kilometre from the city's airport.
Agents from the US Bureau of Alcohol, Tobacco, Firearms and Explosives field office in San Francisco were responding to the shooting, the Bee reported.
It was at least the second fatal gun attack Sunday in southeast Fresno.
A man in his 20s was shot to death early Sunday at a home in another part of the city. Police have not said whether the incidents could be connected.
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