Police killed a knife-wielding assailant who injured three people and took another hostage in an attack Saturday on a Carrefour hypermarket in southern China, state media said.

The man began slashing people early Saturday morning at the French chain's Longquan outlet on the outskirts of Kunming city, the official Xinhua News Agency reported. Police shot and killed him after repeated attempts to convince him to surrender were unsuccessful, it said.

The attacker had been holed up in an office after exchanging his original hostage for a nurse brought in to aid the injured, Xinhua said.

People who answered phones at two of the French chain's other Kunming outlets confirmed the attack but gave few details. Phones at the Longquan store rang unanswered.

A duty officer at the city police headquarters said he had no news about the incident, while an officer at the Longquan district police department said no information would be given out at this time.

The motivation for the attack wasn't known and it wasn't clear if Carrefour had been specifically targeted. The chain, which has 120 stores in China, was picketed by angry Chinese earlier this year following protests as the torch for the Beijing Olympic Games was passing through Paris.

There are indications that random violence is also on the rise in China, with a string of recent stabbings and other attacks blamed on the mentally ill and people suffering from financial problems or social alienation.