KUNMING - Nine people were killed and 36 others injured, including eight seriously, after a coach veered off an expressway section in Southwest China's Yunnan province late Wednesday night, local authorities said Thursday.

The 44-seat sleeper coach had 46 people on board including two drivers, when the accident happened in Nanhua County, Chuxiong Prefecture, at around 11:30 pm Wednesday.

Local authorities confirmed that there were two toddlers under three years old on the coach.

The source said the coach owned by Baoshan Transportation Corp. was en route from the provincial capital of Kunming to Tengchong, a scenic spot in Baoshan city bordering Myanmar, when it bumped on the expressway guardrail on a viaduct linking two expressways and plunged by over 10 meters to the ground.

Rescuers delivered all the injured to a hospital. Only one of the passengers was uninjured in the accident.

An investigation into the accident is under way.