The bus skidded off a highway in Peru's Andean Ayacucho region at dusk, overturning and plummeting down a slope of about 200 meters, Jhonny Rolando Valderrama, head of the highway protection division, told state news agency Andina.

Valderrama said the accident occurred on the Los Libertadores highway in Ayacucho in the south-central Andes and that rescue work was ongoing.

Peru's ground transportation superintendent SUTRAN said in a statement the bus belongs to local company Turismo Molina Union SAC and that it has initiated an investigation.