A knife-wielding man killed two people and injured two others at a primary school in central China on Wednesday, the latest such attack to hit the country in recent years.

Two injured primary school students have been sent to hospital with no danger to their lives, the government of Ningyuan county in Hunan province said in a statement.

Authorities did not state the identities or age of those killed.

Police detained a 31-year-old male suspect, surnamed Zheng, from the town of Baijiapingzhen, where the primary school is located, the statement added.

China has experienced a spate of knife attacks against schoolchildren in recent years, forcing authorities to increase security.

In October, a woman attacked and injured 14 children with a knife at a kindergarten in China's southwestern Sichuan province.

In April 2018, a man killed nine middle school students as they were returning home in one of the country's deadliest knife attacks in recent years.

Earlier this year authorities executed a farmer who slashed young children with a knife at a kindergarten in the southern Guangxi Zhuang region two years ago, seriously injuring four of them.