The first one occurred 19 days into the new year when a man used an ax to kill four family members, including his infant daughter. Five months later, 12 people were killed in a workplace shooting in Virginia. Twenty-two died at a Walmart in El Paso in August.

A database compiled by The Associated Press, USA TODAY and Northeastern University shows there were more mass killings in 2019 than any other year dating back to at least the 1970s.

In all, there were 41 mass killings, defined as when four or more people are killed, excluding the perpetrator. Of those, 33 were mass shootings. More than 210 people were killed.

Most of the mass killings barely became national news, failing to resonate among the general public because they didn’t spill into public places as massacres did in El Paso and Odessa, Texas; Dayton, Ohio; Virginia Beach, Virginia; and Jersey City, New Jersey.

The majority of the killings involved people who knew each other – family disputes, drug or gang violence or people with beefs that directed their anger at co-workers or relatives.

In many cases, what set off the perpetrator remains a mystery.

That’s the case in the first mass killing of 2019, when a 42-year-old man took an ax and killed his mother, stepfather, girlfriend and 9-month-old daughter in Clackamas County, Oregon. A roommate and an 8-year-old girl escaped, and the rampage ended when police fatally shot the killer.

The perpetrator had occasional run-ins with police over the years, but what drove him to attack his family remains unknown. He had just gotten a job training mechanics at an auto dealership, and despite occasional arguments with his relatives, most said there was nothing out of the ordinary that raised red flags.

The incident in Oregon was one of 18 mass killings in which family members were slain, and one of six that didn’t involve a gun. 

Mass killing trends of 2019

•The 41 mass killings were the most in a single year since the AP/USA TODAY and Northeastern database began tracking such events in 2006, but other research going back to the 1970s shows no other year with as many mass slayings. The second-most killings in a year before 2019 was 38 in 2006.

•The 211 people killed in this year’s cases are  outnumbered by the 224 victims in 2017, when the deadliest mass shooting in modern U.S. history took place in Las Vegas.

•California, which has some of the strictest gun laws in the country, had the most mass slayings – eight. Nearly half of U.S. states experienced a mass slaying, from big cities such as New York to tiny towns such as Elkmont, Alabama, which has a population of almost 475 people.

•Firearms were the weapon in all but eight of the mass killings. Other weapons included knives, axes and fire at least twice when the perpetrator set a mobile home ablaze, killing those inside.

•Nine mass shootings occurred in public places. Other mass killings occurred in homes or workplaces.

'This seems to be the age of mass shootings'

James Densley, a criminologist and professor at Metropolitan State University in Minnesota, said the AP/USA TODAY/Northeastern database confirms and mirrors his own research into mass shootings.

“What makes this even more exceptional is that mass killings are going up at a time when general homicides, overall homicides, are going down,” Densley said. “As a percentage of homicides, these mass killings are also accounting for more deaths.”

He said it’s partially a byproduct of an “angry and frustrated time.” Densley said crime tends to go in waves: The 1970s and 1980s saw a number of serial killers, the 1990s were marked by school shootings and child abductions and the early 2000s were dominated by terrorism.

“This seems to be the age of mass shootings,” Densley said.

He and James Alan Fox, a criminologist and professor at Northeastern University, expressed worries about the “contagion effect” – the focus on mass killings fueling other mass killings.

“These are still rare events. Clearly, the risk is low, but the fear is high,” Fox said. “What fuels contagion is fear.”

The mass shootings this year include three in August in Texas and Dayton that stirred urgency, especially among Democratic presidential candidates, to restrict access to firearms.

The database does not have a complete count of victims who were wounded, but among the three mass shootings in August, more than 65 people were injured.

'As soon as the El Paso shooting happened, I was on edge'

Daniel Munoz, 28, of Odessa, was caught in the crossfire of a shooting in West Texas. He was on his way to meet a friend at a bar when he saw a gunman and the barrel of a firearm. He got down as his car was sprayed with bullets.

Munoz, who moved to Texas about a year ago to work in the oil industry, said he had been on edge since the Walmart shooting 28 days earlier and about 300 miles away in El Paso, worried that a shooting could happen anywhere at any time.

He called his mother after the El Paso shooting to encourage her to have a firearm with her in case she needed to defend herself. He told friends before they went to Walmart to bring a firearm in case they needed to protect themselves or others during an attack.

“You can’t just always assume you’re safe. In that moment, as soon as the El Paso shooting happened, I was on edge,” Munoz said.

As a convicted felon, he’s prohibited from possessing a firearm, which adds to his anxiety, he said.

A few weeks later, as he sat behind the wheel of his car, he spotted the driver of an approaching car wielding a firearm. “My worst nightmare became a reality," he said. "I’m in the middle of a gunfight, and I have no way to defend myself.”

In the months since, the self-described social butterfly has steered clear of crowds and can tolerate only so much socializing. He drives the same car, still riddled with bullet holes on the side panels, another bullet hole in the headrest of the passenger seat and the words “evidence” scrawled on the doors. His shoulder is pocked with bullet fragments.

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