At least 34 people were killed and many others wounded after a bus plunged 200 metres down a ravine in northern Peru, police have said.

The bus veered off a mountain road near the town of Otuzco almost 570km north of the capital of Lima, early on Saturday.

"So far, we've recovered 26 bodies, and seven people have been hurt," said Astor Moreno, an official with Otuzco's police force.

The victims of the crash include three doctors, two nurses and several rural school teachers. 

Forty-three passengers were aboard the bus when it left the town of Manchu headed toward the regional capital of Trujillo.

Authorities blamed the region's treacherous, winding roads, the poor condition of the vehicle, and driver error for the accident. 

Road accidents are common in the Peruvian Andes due to poorly maintained roads, inconsistent vehicle maintenance, and the propensity of overworked bus drivers to speed.

In 2011, 1,124 people were killed and 2,583 injured in 1,108 highway accidents, according to the latest official figures.

Source: Agencies