At least nine people were killed in a mass shooting in a city east of Los Angeles following a Lunar New Year celebration that attracted thousands.

Police said the shooting occurred at a business premises in Monterey Park, a city of about 60,000 people with a large Asian population that is about 10 miles from central LA.

The shooting, which happened at an unspecified business on Garvey Avenue, was reported at 10.22pm local time – 6.22am on Sunday in the UK, Sergeant Bob Boese of the Los Angeles County Sheriff’s Department said.

Sgt Boese confirmed that the gunman was male, but no further information was given about whether he was still being sought, had been captured or was among those who had been killed.

Seung Won Choi, who owns a seafood restaurant in the area, told the Los Angeles Times that three people rushed into his business and told him to lock the door.

He said he was told there was a gunman with a machine gun who had multiple rounds of ammunition on him. Mr Choi said he believes the shooting took place at a dance club.

The shooting occurred close to where thousands of people had attended a Lunar New Year celebration. Saturday was the start of the two-day festival, which is one of the largest Lunar New Year events in Southern California.

Videos posted on social media showed people being loaded onto stretchers and placed into ambulances. Other photos showed bloodied and bandaged victims being treated by Monterey Park firefighters in a car park.

The incident marks the fifth mass shooting in the US this month and the deadliest since 21 people were killed in a school in Uvalde, Texas, according to The Associated Press/USA Today database on mass killings in the US. The latest violence comes two months after five people were killed at a Colorado Springs nightclub.