The gunman in the mass shooting in Monterey Park, California, that left 11 people dead is the oldest U.S. mass public shooter in at least six decades, according to researchers who study the topic.
At 72 years old, Huu Can Tran is the oldest person to fatally shoot four or more people in a public space – not including domestic and gang-related disputes – since at least 1966, according to James Densley, co-founder of The Violence Project, a nonprofit research center.
"It's rare to see mass shooters as old as this, unprecedented even, which makes you wonder what happened recently in their life to push them over the edge," Densley said. "A mass shooting is really a final act, which perhaps tells us that this man had reached a point in life where he no longer cared if he lived or died."
Median age for mass shooters is 32
Including domestic disputes, Tran is the second-oldest mass killer, according to a database compiled by USA TODAY, The Associated Press and Northeastern University. In 2011, a 73-year-old man targeted and murdered five people – including his former wife, her lawyer and three of her friends – in Yuma County, Arizona, before killing himself.
California shooting timeline: How the deadly attack at a Monterey Park dance studio unfolded
Police said Tran opened fire at a dance hall late Saturday, hours after Lunar New Year celebrations. He later entered another dance studio in nearby Alhambra, where two people wrestled the firearm him and he fled in a white van, police said.
Tran was discovered Sunday in the van in the nearby town of Torrance. Authorities found him dead of a self-inflicted gunshot, police said.
Relatives say Tran had once given free lessons at the Star Ballroom Dance Studio, where the killings happened. Authorities Monday were still searching for motive in the case.
Tran is two years older than the previous oldest mass public shooter, Densley said. That was in 1981. Mass public shooters are almost always male (98%), and the median age is 32, The Violence Project data shows.
But ages vary by shooting location. Though mass shooters at offices, warehouses and houses of worship skew older, shooters at K-12 schools, colleges and universities tend to be younger, the data shows.
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This article originally appeared on USA TODAY: California mass shooting suspect is oldest in United States history