Four people have been killed after ten were shot at a party in Fresno, California.
A gunman opened fire after entering the back garden of a home at 6pm local time on Sunday (2am GMT).
NBC reporter Dennis Valera tweeted that three people were already dead when officers arrived, while one person died in hospital.
Mr Valera said that the other victims are in hospital with some in a critical condition, while others are critical but stable.
He added that all those shot were adult men.
The shooting is said to have taken place while family and family friends were watching a football game in the garden together.
Police Lieutenant Bill Dooley told NBC’s affiliate KSEE that no arrests have been made after what he described as a “mass casualty shooting” in the southeast of the city.
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Mr Dooley told the Fresno Bee local news site: “Officers arrived on scene – what we found were several individuals deceased in the backyard.
“We do have multiple shooting victims.”
He added: “What we do know is that this was a gathering, a family and friend gathering in the backyard.
“Everyone was watching football this evening when unknown suspects approached the residence, snuck into the backyard and opened fire.”