Five people have been killed and 18 injured in north-eastern China after a car collided with a crowd of children outside a primary school, state media reported.

The driver was taken into custody after the crash at around noon in the coastal city of Huludao in Liaoning province, CCTV said.

Eighteen people were treated in hospital, the reports said, and the cause of the crash was under investigation.

Security camera footage shows a line of children crossing the street in front of their school when a car approaches, changes lanes and swerves into the children.

It is not known if the incident was a deliberate attack.

Last month, a man drove a vehicle into a crowd of pedestrians in the eastern city of Ningbo, killing two people and wounding 16.

In September, 11 people were killed and 44 injured when a man drove a vehicle deliberately into people at a plaza in the central province of Hunan before jumping out and attacking victims with a dagger and shovel.

Other deadly attacks have occurred at schools, including several in 2010 in which nearly 20 children were killed, prompting a response from top government officials and leading many schools to increase security.

In June, a man used a kitchen knife to attack three boys and a mother near a school in Shanghai, killing two of the children. Last year, police said a man set off an explosion at the front gate of a kindergarten in eastern China, which struck as relatives gathered to pick up their children at the end of the day, killing eight people.