BEIJING — Dozens of people have been killed in China in the past three months in a series of mass attacks. Most recently, on Tuesday, primary school students were hit by a car while arriving to class.

Attacks take one of two forms: either drivers mowing down people on foot, or knife-wielding attackers stabbing multiple victims. Guns are strictly restricted in China, and gun attacks are rare.

The attackers appear to be taking out their anger and frustration over a personal issue, according to police reports. The victims are often unknown to them.

Such attacks are not new in China and have targeted kindergartens and other schools in the past. The recent increase has attracted the attention of authorities and the public. Here’s a look at some of the recent events.

November 19: A vehicle hits students at the primary school gate

A small white SUV hit students arriving for classes at Yong’an Elementary School in Changde, a city in the interior of China’s Hunan Province. Several adults were also injured, the official Xinhua news agency said.

Security agents and parents subdued the driver, Xinhua said. Authorities later issued a brief statement saying the 39-year-old driver had been taken into custody. Few details about the incident have yet been confirmed.

Nov. 16: Sta

bbing kills eight at vocational school

Eight people were killed and 17 others injured in a knife attack at the Wuxi Vocational Institute of Arts and Technology in the city of Yixing, about 160 kilometers (100 miles) west of Shanghai in eastern China.

The police detained a 21-year-old student. They said he failed his exams and couldn’t graduate and was unhappy with his internship salary. He decided to vent his frustrations through the attack, a police statement said.

November 11: A driver kills 35 at a sports complex

A man who authorities said was angry over his divorce settlement plowed his car into a crowd of people exercising at a sports complex in the southern Chinese city of Zhuhai, killing 35 people and injuring 43 others.

Police detained the 62-year-old man, who they said was in his car trying to stab himself with a knife. He later fell unconscious due to neck and other injuries. They said the man was unhappy with the division of financial assets during his divorce.

October 28: Five injured in knife attack near primary school

A knife attack near a prominent primary school in Beijing has injured five people, including three children. Police detained a 50-year-old suspect. No reason was given.

In early October, a 10-year-old Japanese student died after being stabbed near his school in Shenzhen, a southern city that borders Hong Kong. It followed a knife attack in June on a Japanese woman and her child at a bus stop for a Japanese school in Suzhou, a city near Shanghai.

September 30: Knife attack kills three in a supermarket

A 37-year-old man allegedly killed three people and injured 15 others with a knife in a supermarket in Shanghai. Police said the man had personal financial disputes and had come to Shanghai to “vent his anger”.

The attack took place on the eve of a week-long national holiday in a suburban district of Shanghai, China’s financial hub.