Four passengers were killed and another 13 injured Thursday after a bus turned over on an expressway in southwest China's Guizhou Province, police said.

The accident occurred at about 9 a.m. The bus, with 53 passengers on board, was heading for Sichuan Province, according to officials of Guizhou Provincial Public Security Department.

All the injured were rushed to No. 2 People's Hospital of Guiding County. One was in critical condition.

Initial investigation showed the bus ran too fast on the slippery road at a sharp turn, according to the police.

The driver was injured in the accident, police said.

(Xinhua News Agency January 1, 2009)