The other 20 people were being treated for injuries and emergency responders were dispatched to the scene, police said, without providing any more details.
The accident happened in Qiannan prefecture — a poor, remote and mountainous part of Guizhou, home to several ethnic minorities.
Two social media posts by the China Road Network monitoring service, which have since been deleted, said the accident occurred at around 2:40am (1840 GMT on Saturday), according to screenshots circulating on the Twitter-like Weibo.
Social media users angrily demanded why a passenger bus was travelling down a highway in the early hours of the day when many major roads in the province have been closed to regular traffic.
“This feeling can’t simply be represented by lighting a candle and saying RIP,” read one Weibo post with more than 15,000 likes.
One hundred toll stations are shuttered in Guizhou because of Covid-19 restrictions and long-distance passenger journeys across China are banned from running between 2am and 5am.
Guizhou is in the midst of a Covid outbreak that has seen more than 900 new infections in the past two days alone.
Its provincial capital Guiyang, home to six million residents, was locked down earlier in September.
The bus was travelling south in the direction of Guiyang to Libo county, according to the police statement.
Unverified photos circulating widely on social media Sunday showed a gold-coloured passenger bus, whose top is
Road accidents are common in China, where traffic regulations are often flouted or go unenforced. A majority of accidents occur due to violations of traffic laws. China’s frequently overcrowded long-distance buses are particularly prone to fatalities
