A gunman killed 10 people at a Californian ballroom dance studio during a day of Lunar New Year celebrations and then may have tried, but failed, to target a second dance hall, authorities have said.

An urgent search was under way across the Los Angeles area for the suspect.

Los Angeles County Sheriff Robert Luna said that 20 to 30 minutes after the shooting at the Star Ballroom Dance Studio in Monterey Park late on Saturday – which left five women and five men dead and another 10 people injured – a man with a gun had entered the Lai Lai Ballroom in nearby Alhambra. Mr Luna said it remained unclear whether the events were connected.

“We believe that there’s an incident that may be related,” Mr Luna said of the incident in Alhambra. “We’re not quite there yet, but it’s definitely on our radar screen.”

Mr Luna said that a “male Asian suspect” had entered the Alhambra club with a “firearm” and that people had wrestled the gun away from him before he fled.

Investigators are interested in a white cargo van that was seen in the area, and police have the gun from Alhambra.

Mr Luna did not reveal what type of gun was recovered in Alhambra, and said that investigators believed the firearm used in Monterey Park was not an “assault rifle”.

Police officers stand outside a ballroom dance club in Monterey Park
Police officers stand outside a ballroom dance studio in Monterey Park (Jae C Hong/PA)

The massacre – which derailed Lunar New Year celebrations and sent fear through Monterey Park and Alhambra’s large Asian-American communities – was the nation’s fifth mass killing this month.

Monterey Park is a city of about 60,000 people on the eastern edge of Los Angeles and is composed mostly of Asian immigrants from China or first-generation Asian Americans.

The shooting happened in the heart of the city centre where red lanterns decorated the streets for the Lunar New Year festivities. A police car was parked near a large banner that read “Happy Year of the Rabbit!”

The celebration in Monterey Park is one of California’s largest and had attracted tens of thousands of people throughout the day.

An investigator outside Star Dance Studio in Monterey Park
An investigator outside Star Dance Studio in Monterey Park (Jae C Hong/AP)

Two days of festivities, which have been attended by as many as 100,000 people in past years, were planned. But officials cancelled Sunday’s events following the shooting.

Tony Lai, 35, of Monterey Park was stunned when he came out for his early morning walk to learn that the noises he had heard in the night were gunshots.

Los Angeles County Sheriff Robert Luna briefs the media outside the Civic Centre in Monterey Park
Los Angeles County Sheriff Robert Luna briefs the media outside the Civic Centre in Monterey Park (Damian Dovarganes/AP)

“I thought maybe it was fireworks. I thought maybe it had something to do with Lunar New Year,” he said. “And we don’t even get a lot of fireworks here. It’s weird to see this. It’s really safe here. We’re right in the middle of the city, but it’s really safe.”

The incident marked not just the fifth mass killing in the US since the start of the year but also the deadliest since May 24, when 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 database also showed that 2022 was one of the nation’s worst years in terms of mass killings, with 42 such attacks — the second-highest number since the tracker was created in 2006.

A law enforcement helicopter hovers over Star Dance Studio in Monterey
A law enforcement helicopter hovers over Star Dance Studio in Monterey (Jae C Hong/AP)

The White House said US president Joe Biden had been briefed on the situation by homeland security adviser Elizabeth Sherwood-Randall.

Meanwhile, authorities in Louisiana said 12 people had been injured in a shooting at a nightclub in Baton Rouge early on Sunday.

One of the victims was in a critical condition, while the rest were listed as stable, police said. No arrests had been made.

The shooting occurred inside the Dior Bar & Lounge at around 1.30am, Sergeant L’Jean McKneely Jr, a police spokesman, said.

Although the motive for the shootings was unknown, Mr McKneely said the police department did have leads.