NANNING - Six people, including a five-year-old girl, have been confirmed dead and nine more injured in a six-vehicle pile-up Saturday in South China's Guangxi Zhuang autonomous region, local police said Sunday.

The accident happened at around 1 pm on the Nandan county section of a national highway?in Hechi city when a truck overturned and collided with another truck. The crash quickly developed into a pile-up that also involved four sedans, the county police authorities said in a statement.

Four people, two more than the number reported Saturday, were killed at the scene. Another two died on the way to hospital. Among the dead is a 5-year-old girl, according to the statement.

Nine injured have been sent to a hospital for emergency treatment, it added.

Local police authorities are investigating the cause of accident and further checking the deaths and injuries.