The list of U.S. mass shootings continues to grow.

The mass shooting that left at least 10 dead in Monterey Park, California, on Saturday night is the deadliest in the United States since the massacre in Uvalde, Texas, last May, which killed 19 children and two teachers.

Saturday’s shooting is also the second major attack in less than a week in California. Last Monday, gunmen killed six people in Tulare County, California, including a 16-year-old girl and her 10-month-old son, in a shooting that police say was likely gang-related.

There is no consensus on what constitutes a mass shooting, complicating efforts by the government, nonprofits and news organizations to document the scope of the problem. He gun violence fileA nonprofit research group defines a mass shooting as one that involves at least four people being killed or injured.

By that measure, there have been 33 mass shootings so far in 2023, according to the group. counted 648 mass shootings last year, 21 of which involved five or more deaths.

Here is a partial list of recent mass shootings in the United States:

A Walmart employee opened fire in a break room as the store was preparing to close for the night, killing six people, authorities said. The gunman was found dead, apparently from a self-inflicted gunshot wound, according to police.

Five people were killed and 17 wounded by gunshots in a shooting at an LGBTQ nightclub. The gunman was injured and was taken to a hospital.

Three University of Virginia students, all members of the football team, were killed and two injured when a gunman, a former player, opened fire in a garage after a field trip to see a play in Washington.

A gunman, described by authorities only as a “white minor,” killed five people, including an off-duty police officer, and wounded two others. The attacks sparked a large law enforcement response in the residential area near the Neuse River Greenway, a popular bike trail for Raleigh residents.

Memphis was effectively locked down during an hour-long manhunt for a 19-year-old gunman who killed four people while streaming some of the violence on Facebook Live. The violence involved several shootings and carjackings over the course of the day.

Seven people were killed and dozens more injured when a gunman opened fire from the roof of a building in Highland Park, a northern suburb of Chicago, during a Fourth of July parade. A 21-year-old was arrested several hours later.