At least seven people were killed and 37 were injured Thursday when a passenger bus crashed and turned over in Peru's mountainous Andean region, media reports said.The accident in northern Cajamarca province occurred around 1.45 a.m. after the bus carrying 43 passengers reportedly rear-ended a trailer truck that tried to cut it off at a sharp curve, Peru's Andina news agency quoted rescue workers as saying, according to Xinhua. The incident took place along the highway that links Cajamarca' s southern city of Cajabamba with Trujillo, the capital of La Libertad province, according to the highway police and fire department. The cities are some 250 km apart.The bus driver, Marcos Orlando Leiva Rojas, 33, suffered bruises.Authorities are investigating the crash.