China school stabbing attack: Children suffer 'knife wounds to head' as 20 injured in Beijing

All 20 children taken to hospital, with three badly injured

File image of paramilitary police officers in Beijing (AFP/Getty Images)

Chinese authorities say a man has injured 20 children, three of them seriously, in an apparent knife attack on a primary school classroom in Beijing.

A male suspect was arrested at the scene and an investigation into what happened has begun, according to the government of Xicheng, a major district of the capital.

All the children were taken to hospital and the three who were badly injured were in a stable condition.

The local authorities would not comment on whether a weapon was used in the attack, but posts on social media said some of the children suffered knife wounds to the head.

A witness told the Reuters news agency that there was a significant police presence outside a hospital near the school.

Violent crime is rare in China but there has been a series of knife and axe attacks in recent years, many targeting children, and many schools have beefed up security in response.

In January 2017, a man in southern China stabbed 12 children with a vegetable knife. Prosecutors said the man's motivation was to extract revenge for his life not going as he wanted, as well as a dispute with a neighbour.

The man was executed this month.

Last April, nine people were killed outside a middle school in northwestern China, allegedly by a former student seeking revenge for having been bullied. And in November, five people were killed when a car plowed into a crowd of children outside a northeastern Chinese nursery school.