LIMA, Nov. 5 -- At least 18 people were killed and another 39 injured when a bus crashed with another vehicle in the southeastern Peruvian province of Puno, the National Police of Peru (PNP) said Monday.

According to its report, the accident occurred Sunday night in the region located 1,500 kilometers south of Lima, when the bus was en route from the city of Yunguyo to Tacna on the Pacific coast.

Teams of rescue personnel and residents of the area provided first aid to the injured, who were later transferred to the Manuel Nunez Butron Regional Hospital in Puno.

According to the police report, three people died due to the severity of their injuries in the hospital.

The bus involved in the accident belongs to the passenger transportation company Expreso Yunguyo which operates the route between Puno and the coastal city of Tacna.

Peruvian authorities have opened an investigation into the cause of the accident.