A bus collision killed 13 people and injured 75 others in south China's Guangxi Zhuang Autonomous Region on Saturday, local authorities said.

The accident took place at 6:51 a.m Saturday on a highway in the Yao Autonomous County of Du'an in Guangxi's Hechi City, when two buses bumped into each other, said a spokesman with the Guangxi Regional Administration of Work Safety.

Eleven people were killed on the spot and two others died after emergency operation failed, the spokesman said.

Seventy-five people were left injured and were rushed to a local hospital. Currently, 50 of them are still in hospital for further medical treatment, including four suffering serious injuries, he said.

Initial investigations show that one of the bus is owned by a tourism company in southwest China's Guizhou Province, and the other belongs to another tourism company in southwest China's Chongqing Municipality.

The Guizhou-registered bus carried 41 people and the Chongqing-registered bus carried 48 when the accident happened, according to the two drivers Wan Degang and Xie Bin.

The two buses collided when the Guizhou bus, driven by Wan, took up the lane of the opposite direction, investigations show.

Local authorities are further probing into the accident.