More than 30 people have been killed in a bus crash on a mountain road in Bolivia, police say.

The driver likely lost control of the vehicle, causing it to plunge almost 800 meters (2625 ft) in the southwestern district of Yocalla, an officer said.

Fourteen were also injured, including four children, an official from a local hospital said in a video.

Bolivia has notoriously dangerous roads, particularly in mountainous areas.

The accident happened between the cities of Potosi and Oruro, police said.

Officials believe that the crash could have been caused by speeding, with the driver "unable" to control the bus, police colonel Victor Benavides told the AFP news agency.

This is believed to be the most serious road accident reported in the South American country so far this year.

Local news outlet Unitel reported that several of those injured are in a serious condition.

Deadly road accidents are common in Bolivia.

Last month, 19 people were killed when another bus came off a road, also near Potosi.

Road accidents kill an average of 1,400 people every year in the country of about 12 million inhabitants, according to government data.