A Chinese man has rammed his car into a group of schoolchildren, injuring 13, state media have said.

The man reportedly packed his car with firecrackers and a gas tank and tried to set the vehicle alight.

State-run Jinghua Times said the students, in the northern Hebei province, were leaving school for a lunch break when the car hit them.

China has seen several attacks on schools in recent years, including a knife attack two weeks ago.

In the latest incident, three children were seriously hurt and 10 others were treated for minor injuries, Xinhua news agency said.

The Xinhua report named the man as Yin Tiejun, 48, and said his daughter had been murdered three years ago.

He apparently told police he had been dismayed after a court failed to jail all of his daughter's killers.

Police said Mr Yin had tried to set his car on fire with a bottle of diesel after crashing into the children.

But he denied the firecrackers and gas tank were part of an attempt to cause an explosion.

The incident, at Fengning middle school, happened on Monday but was only reported later on Tuesday.

A spate of deadly incidents at schools in 2010 sparked nationwide panic.

Several of the attackers appeared to be men with grievances against the authorities.

Officials characterised them as mentally disturbed men.