Shooters shared oddity in common: They were elderly

The gunman who killed 11 people in Monterey Park, Calif., on Saturday and the man suspected of killing seven people in the Half Moon Bay area on Monday are among the oldest suspected mass shooters in U.S. history, according to the Violence Project, a nonprofit organization that studies firearm-related bloodshed.

Authorities say that 67-year-old Zhao Chunli is responsible for Monday’s deadly shootings in two separate plant nurseries in the area. They arrested him and are questioning him to find out his motive.

Huu Can Tran, the Monterey Park gunman, was 72. He shot and killed himself inside a vehicle following a police manhunt. His motive is not known.

This makes Tran the oldest person accused of carrying out a mass shooting at a public venue in U.S. history, and the second septuagenarian in about four decades to carry out such a massacre.

The median age is 32, according to the Violence Project.

“His age is definitely an outlier,” James Densley, a criminal justice professor at Metropolitan State University in St. Paul, Minn., who co-founded the Violence Project, previously told The Washington Post.

By that organization’s definition, previously the oldest person to stage such a public massacre was William Bevins, who at age 70 killed five men with an automatic rifle in a Kentucky auto parts store in 1981.

At 67, Zhao is younger than Tran — but he is still far older than the median age of the mass shooters included in the Violence Project’s database.

The Violence Project collects data on the characteristics of attackers who kill at least four people in shootings that last no more than a day in public spaces. The Washington Post defines a mass killing as an event in which four or more people, not including the shooter, have been killed by gunfire. It does not consider other factors such as location or motive.