At least 35 people were killed and 43 more injured after a car ploughed into a crowd of people exercising outside a stadium in Zhuhai, China, according to authorities.
A 62-year-old male driver, surnamed Fan, is alleged to have driven an SUV into Zhuhai Sports Centre, local police said in a statement.
Chinese media reported that many elderly people, as well as teenagers and children, were among the injured.
Fan was arrested while trying to flee, police said, and is currently in a coma as a result of self-inflicted wounds.
The incident took place despite heightened security in the city, which is hosting a major civil and military airshow.
Police preliminarily determined that the ramming attack was triggered by Fan’s dissatisfaction with the outcome of a property settlement following his divorce.
Due to his coma, he is unable to be questioned by the authorities.
Most videos of the incident posted by eyewitnesses had been scrubbed off Chinese social media by Tuesday morning, but some footage still circulating online showed many people lying on the ground and being attended to by paramedics and bystanders.
An eyewitness, Mr Chen, told Chinese news magazine Caixin that at least six groups of people had gathered at the stadium for their regular walks when the incident happened.
The groups use a designated walking path that traces the stadium’s perimeter.
Mr Chen said his group had just completed its third lap around the stadium when a car suddenly charged towards them at a high speed, “knocking down many people”.
It is unclear whether the incident was linked to the high-profile Airshow China, which started on Tuesday at a venue just 40km (24 miles) away from the stadium. China is showcasing its latest warplanes and attack drones at the show, and top Russian official Sergei Shoigu is expected to attend.
Several entrances and exits to the sports centre have been closed during the airshow to facilitate “control”, the centre’s management said on Tuesday.
Chinese president Xi Jinping expressed his deep concern over the incident, instructing authorities to make every effort to treat the injured and calling for the perpetrator to be severely punished.
In response, the central government dispatched a working group to help guide the handling of the incident.
Investigations into the case, as well as treatment of the injured, are ongoing.
China has seen a spate of violent attacks on members of the public in recent months.
In September, a man went on a stabbing spree at a supermarket in Shanghai, killing three people and injuring several others.
In that same month, a 10-year-old Japanese student died a day after he was stabbed near his school in southern China.
