At least 10 people were killed and more than 30 injured in New Orleans in the early hours of New Year’s Day, when a man deliberately plowed a pickup truck into crowds on Bourbon Street, local officials said.

Authorities are investigating the attack as an act of terrorism.

The incident is the latest in a long string of vehicle- based attacks against crowds, dating back decades. Vehicle ramming did not start as a terrorist tactic, but it has frequently been used by extremist organizations and radicalized individuals to kill, injure and instill fear.

Why vehicles are used as weapons

Cars and trucks are ubiquitous, especially in the developed world, and can easily be repurposed into deadly weapons.

Assailants with “limited access to explosives or weapons” can use vehicles to cause great harm “with minimal prior training or experience,” according to an FBI handout on “Terrorist Use of Vehicle Ramming Tactics.”

Attacks with vehicles transform “a bland, everyday object into a lethal, semi-strategic weapon,” researchers Vincent Miller and Keith Hayward wrote in a 2019 study published in The British Journal of Criminology. The tactic gives “marginal actors” the ability to “strike at the heart of urban centers and sow fear in the wider society,” they added.

After potential targets such as airports and public buildings became more heavily secured, especially after the Sept. 11, 2001, attacks, some terrorists and other assailants began to use vehicles against more vulnerable targets, such as groups of people congregating in public spaces.

history of attacks

Using vehicles to indiscriminately attack people has a long history, mostly unrelated to organized terrorism, such as the 22-year-old Czechoslovak woman who killed eight people in 1973, citing her grievances against society.

Terrorist groups began using ramming attacks in the 1990s, according to a study by the Mineta Transportation Institute, part of San Jose State University.

The majority of the 184 vehicle-ramming attacks between 1963 and mid-2019, when the study was published, took place in Israel and the West Bank.

Islamic groups: In a 2010 article in its magazine, Inspire, al-Qaida encouraged adherents to use vehicles “to mow down the enemies of Allah.” But the tactic did not really catch on until several years later, when the Islamic State group, or IS, began to call for vehicle attacks.

New York City: A man drove a pickup into a crowded bike path in 2017 along the Hudson River in Manhattan, killing eight and injuring at least 11 before he was shot by police. Notes found near the scene indicated the killer’s allegiance to IS, authorities said.

Nice, France: More than 80 people were killed and hundreds injured when a man drove a 19-ton truck through a crowd of spectators watching Bastille Day fireworks in southern France. Investigators said the driver had been self-radicalized by watching jihadi videos, with no evidence linking him directly to IS.

Charlottesville, Virginia: A man drove his car into a crowd of people protesting a gathering of white supremacists, killing one woman and injuring nearly 40 other people. He was convicted of first-degree murder.

Christmas markets: In 2016, a man killed 12 people by driving a truck into a crowd in central Berlin. In December, a man drove into a crowd in the eastern city of Magdeburg, Germany, killing at least five people, including a 9-year-old.

Stopping the attacks

As vehicle-based attacks have become more common, police and security forces have tried to make public spaces a tougher target, erecting barriers such as bollards — short, sturdy posts that are designed to stop a car or truck before it can reach a crowd or a building.

But recent events have shown how difficult it can be to eliminate the threat.

Germany began strengthening security measures around its seasonal Christmas markets after the 2016 attack in Berlin.

However, the assailant in Magdeburg evaded protective measures and drove into a crowded market, injuring hundreds in addition to those killed.

“The problem in the most recent case is that the perpetrator used a lane reserved for ambulances,” said Nicolas Stockhammer, a professor of security studies at Danube University in Krems, Austria. “He approached the area through a side where there was no protection.”