At least 25 people died and more than a dozen were injured when a bus plunged into a ravine from a mountain road in northern Peru, local authorities said Monday.

Local official Olga Bobadilla told RPP radio the incident late Sunday happened on a potholed dirt road in the Andean region of Cajamarca, "and the bus fell into an abyss" some 200 meters (some 650 feet) deep.

The toll was updated from an initial 23 to 25 later in the day.

The bus with more than 50 passengers ended up on the edge of a river, and some of those on board were swept away by the water, municipal official Jaime Herrera said.

Rescue workers and firefighters were at the scene of the crash, from where the injured have been evacuated to hospital.

The Celendin municipality declared 48 hours of mourning as dozens of people, many crying, gathered at a police station near the accident scene, desperate for news of their loved ones.

Accidents are frequent on Peruvian roads due to speeding, poor road conditions, lack of signs and poor enforcement of traffic rules.

Last year, the country registered more than 3,100 deaths from traffic accidents.

Authorities are investigating whether the bus was roadworthy.