At least two assailants armed with knives attacked people at a train station in southern China on Friday, injuring nine, and police fatally shot one of the suspects, officials said.

The second suspect was captured, police in the city of Guangzhou said in a statement. The incident was still under investigation and a motive has not been determined, police said.

The official Xinhua News Agency said one of the officers who fired shots was injured in the thumb, but it was not immediately clear how he was injured. Xinhua also reported that one of the assailants chased a woman and a child who fell.

Photos and video posted on social media reportedly showed the attack took place in a square outside the station. One video showed a man hacking near a vendor stall with a cleaver while a security officer approached with a long baton. Several photos showed blood smeared in several places on the rain-soaked pavement.

The attack came during a period of heightened sensitivity because of the March 5-15 meeting in Beijing of China's ceremonial legislature, the National People's Congress.

A knife attack at a train station in the southern city of Kunming about a year ago claimed 29 lives. Authorities blamed separatists from the western province of Xinjiang.

Another knife attack injured six people at the same Guangzhou train station in May of last year.

China has also suffered a spate of knife attacks on schoolchildren carried out by people lashing out over personal problems.