MONTEREY PARK, Calif. >> Investigators searching for a motive in the largest mass shooting in Los Angeles County history say a search of the suspected gunman’s home discovered a rifle, hundreds of rounds of ammunition and evidence he was manufacturing gun silencers.

Los Angeles Sheriff Robert Luna said investigators have not yet established Huu Can Tran’s motive in the massacre during a celebration of Lunar New Year at a Monterey Park dance hall.

“What drove a madman to do this? We don’t know, but we intend to find out,” Luna said.

The 72-year-old Tran fired 42 rounds at the Star Ballroom Dance Studio, where 11 people were killed and nine wounded.

Tran then drove to another nearby dance hall where Brandon Tsay, who works at the establishment started by his grandparents, wrested a weapon away from him and saved “countless lives,” Luna said.

“He’s the hero that disarmed the suspect,” Luna said. “What a brave man he is.”

Tsay took a 9 mm semi-automatic assault weapon from Tran at the Lai Lai Ballroom, Luna said.

Tran was later found dead in his van from a self-inflicted gunshot wound.

He had a previous conviction for unlawful possession of a firearm in 1990 and otherwise a limited criminal history, Luna said.

Los Angeles County Supervisor Janice Hahn said it was the deadliest mass shooting in LA County.

THIS IS A BREAKING NEWS UPDATE. AP’s earlier story follows below.

MONTEREY PARK, Calif. (AP) — The search for the motive behind the shooting massacre that killed 11 people at a Los Angeles-area dance hall led police to a mobile home community as they probed the past of the 72-year-old suspect Monday and his relationship to the ballroom.

Sheriff’s deputies from Los Angeles County searched the home in a gated senior community where Huu Can Tran lived in the town of Hemet, an hour’s drive from the scene of the crime in Monterey Park, Hemet police spokesperson Alan Reyes told The Associated Press.

Monterey Park Police Chief Scott Wiese said he wasn’t aware of the search results or if Tran, who died of a self-inflicted gunshot wound, left behind any note indicating what drove him to shoot up the dance hall.

“We all want answers to questions that we may never have answers to,” Wiese said. “That’s kind of the enigma of this. I know that my individual officers would like to know why. I know the families want to know why. The why is a big part of this. The problem is, we may never know the why.”

Tran had visited Hemet police twice this month to report he was the victim of fraud, theft and poisoning by family members a decade or two ago in the LA area, Reyes said. Tran said he would return to the station with documentation but never did.

He was found dead Sunday in the van that he used to flee after attempting to attack a second dance hall, authorities said. The mayor of Monterey Park said Tran may have frequented the first dance hall that he targeted, and his ex-wife told CNN she had met him there and he offered her free lessons.

The death toll rose to 11 Monday after health officials announced that one of the 10 people wounded had died, the LA County Department of Health Services said.

Officials did not disclose any information about the 11th fatality, but all except one of the others were 60 or older, according to information released Monday by the Los Angeles coroner’s office providing the first identifications.

My Nhan, 65, Lilian Li, 63, and Xiujuan Yu, 57, were the three women named. Two other women were in their 60s, and one was in her 70s. Valentino Alvero, 68, was the only man identified. Three men in their 70s and one in his 60s were also killed.

Nhan’s family said in a statement that she was a loving person whose kindness was contagious, and was a regular at the Star Ballroom Dance Studio.

“It’s what she loved to do. But unfairly, Saturday was her last dance,” the family said. “We are starting the Lunar New Year broken. We never imagined her life would end so suddenly.”

Authorities have shared little about Tran, who once owned a trucking company, according to California business records.

Tran’s Trucking Inc. was based in Monterey Park and licensed with the state from September 2002 through August 2004.

Los Angeles Superior Court records show he was married in 2001 and divorced five years later, citing irreconcilable difference. The couple did not have children, said they had no community property and neither side had to pay alimony.

In the uncontested case, Tran noted in a filing that he could not get away from work to attend any court hearings, though he did not disclose where he worked or what he did.

His ex-wife told CNN that they married soon after they met at the dance hall. While she is named in court papers, she asked not to be identified because of the sensitivity of the case.

She said he would become upset if she missed a step dancing, but was never violent toward her.

Tran eventually moved from the San Gabriel Valley, a melting pot for Asian immigrants, and settled in Hemet, a low-income community of many retirees 75 miles (120 kilometers) east of Los Angeles in Riverside County.

Tran lived in The Lakes at Hemet West, a gated community off a busy road with a view of snow-covered mountains. The development boasts of amenities including a 9-hole golf course, a shuffleboard court and a dance floor. Properties listed for sale ranged from $45,000 to $222,000.

Hemet police had no records of any incidents involving Tran in the community or calls for service at his home, Reyes said.

The shootings during Lunar New Year celebrations sent a wave of fear through Asian American communities and cast a shadow over festivities nationwide.

The massacre 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.

“We do understand that he may have had a history of visiting this dance hall and perhaps the motivation has to do with some personal relationships. But that’s something that I think investigators are still uncovering and investigating,” said Monterey Park Mayor Henry Lo. Public records show Tran once had addresses in the city and neighboring ones.

The mayor and LA County Sheriff Robert Luna stressed that the motive for the attack remained unclear. No other suspect was wanted, according to the sheriff.

The suspect was carrying a semi-automatic pistol with an extended magazine, and a second handgun was discovered in the van where Tran died, Luna said.

Tran is the second-oldest mass killer in the U.S. over the last nearly 20 years according to a database compiled by The Associated Press, USA Today and Northeastern University. The only older mass killer was a 73-year-old who murdered five people in Yuma County Arizona in 2011 before killing himself. The database tracks every mass killing — defined as four dead not including the offender — committed in the U.S. since 2006.

Within three minutes of receiving the call, officers arrived at the Star Ballroom Dance Studio in Monterey Park, according to Monterey Park Police Chief Scott Wiese.

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.

While Luna told reporters on Sunday that two people wrested the weapon away from the attacker, Tsay, who works a few days a week at the dance hall his grandparents started, security footage shown on “Good Morning America” showed only the two men struggling for the gun.

Associated Press journalists Andrew Dalton, Jae C. Hong and Eugene Garcia in Los Angeles and Julie Watson in San Diego contributed to this report.