MONTEREY PARK, Calif. - Authorities searched for a motive for the gunman who killed 10 people at a Los Angeles-area ballroom dance club during Lunar New Year celebrations, slayings that sent a wave of fear through Asian American communities and cast a shadow over festivities nationwide.

The suspect, 72-year-old Huu Can Tran, was found dead of a self-inflicted gunshot wound on Sunday in the van that authorities say he used to flee after being prevented from attacking another dance hall. A man whose family runs the venue confronted the assailant in the lobby and wrested the gun from him, The New York Times reported.

The massacre in Monterey Park was the nation’s fifth mass killing this month - and it struck one of California’s largest celebrations of a holiday observed in many Asian cultures, dealing another blow to a community that has been the target of high-profile violence in recent years.

It was also the deadliest attack since May 24, when 21 people were killed in an elementary school in Uvalde, Texas.

Very little is known about Tran or his connection to the targeted community and dance halls. Public records show he once had addresses in Monterey Park and neighboring cities.

But Los Angeles County Sheriff Robert Luna said the motive remained unclear for the attack, which also wounded 10 people. Speaking at a Sunday evening news conference, Luna said all of the people killed appeared to be over 50. No other suspects were at large, according to the sheriff.

Monterey Park Police Chief Scott Wiese said Sunday evening that within three minutes of receiving the call, officers arrived at the Star Ballroom Dance Studio in Monterey Park. There, they found carnage inside and people trying to flee through all the doors.

“When they came into the parking lot, it was chaos,” Wiese said.

About 20 minutes after the first attack, the gunman entered the Lai Lai Ballroom in the nearby city of Alhambra.

Brandon Tsay was in the lobby at the time, and he told ABC’s “Good Morning America” that he thought he was going to die.

“Something came over me. I realized I needed to get the weapon away from him, I needed to take this weapon, disarm him or else everybody would have died,” Tsay said. “When I got the courage, I lunged at him with both my hands, grabbed the weapon and we had a struggle.”

Once Tsay seized the gun, he pointed it at the man and shouted: “Get the hell out of here, I’ll shoot, get away, go!”

The assailant paused, but then headed back to his van, and Tsay called the police, the gun still in his hand.

Witnesses said the suspect fled in a white van. The van was found in Torrance, another community home to many Asian Americans.

After surrounding the vehicle for hours, law enforcement officials swarmed and entered it. A person’s body appeared to be slumped over the wheel and was later removed. Members of a SWAT team looked through the van’s contents before walking away.