At least 35 people have been killed after a bus veered off a mountain road and plunged into a ravine in southern Peru.

The country’s interior ministry said the bus left the Pan-American Highway and tumbled 80 metres down a jagged slope in the southern region of Arequipa.

At least 20 other passengers have been injured.

Arequipa police chief General Walter Ortiz said: "So far the bus accident has left 35 dead and 20 injured."

It is understood there were only 45 people registered as passengers on the bus.

On Twitter, the Arequipa governor Yamila Osorio said: "Rescue teams have been working since dawn, coordinating the transfer and care of the injured."

The injured were taken to hospital in the city of Camana with three seriously injured passengers transferred by helicopter to regional capital Arequipa.

The bus, operated by the Rey Latino company, had left the coastal town of Chala for Arequipa about four hours before the accident.

It was the second major accident on Peru's roads this year.

On 2 January, a bus crashed into a ravine in the country's central coastal area, leaving 52 dead.