Seven people were killed and five others were injured Thursday in a multi-vehicle crash on highway in south China's island province of Hainan, police said.

The massive crash, which involved four trucks and a MPV, occurred at around 5:40 a.m. on a section of highway in Danzhou City, said a spokesman with the city's traffic police department.

One among the injured was severely wounded and the other four people are in stable condition, he said.

Police are still investigating the cause of the accident.