SHANGHAI (Reuters) - A knife-wielding man has killed two people and injured nine in a Wal-Mart supermarket in the southern Chinese city of Shenzhen, the official Xinhua news agency reported, citing local police.

Xinhua said the injured had been sent to hospital but did not give any details of the victims from the attack on Sunday evening.

It said the attacker, whose surname it gave as Jiang, had been detained and police were investigating.

Violent crime is rare in China compared with many other countries but there has been a series of knife and axe attacks in recent years, many targeting children.

In May, two people were killed in southwest China by a knife-wielding man suspected of suffering from mental illness.