According to Los Angeles County Sheriff’s Department Sergeant Bob Boese, the shooting, which happened late on Saturday, took place at a Monterey Park store on Garvey Avenue.
Police said the male suspect is still at large.
The police announced that Sunday’s Lunar Year celebrations in Monterey Park have been canceled due to the shooting and out of respect for the victims.
Monterey Park, a city of roughly 60,000 people located about 16 kilometers (10 miles) from downtown Los Angeles, has a sizable Asian population.
“Our hearts go out to those who lost loved ones tonight in our neighboring city, Monterey Park, where a mass shooting just occurred,” Los Angeles City Controller Kenneth Mejia said in a tweet.
Seung Won Choi, who owns the Clam House seafood barbecue restaurant across the street from where the shooting happened, told the Los Angles Times that three people rushed into his business and told him to lock the door.
The people also told Choi that there was a shooter with a machine gun who had multiple rounds of ammunition on him so he could reload.
Choi said he believes the shooting took place at a dance club.
Saturday was the start of the two-day festival, which is one of the largest Lunar New Year events in southern California.
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 AP/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.