At least 39 people were killed when a passenger bus traveling at high speed plunged into a ravine in south-western Pakistan on Sunday, the German Press Agency (dpa) quoted officials as saying. The incident occurred in Balochistan province's Lasbela district when the driver of the bus carrying around 48 people lost control and hit a bridge pillar, sending the bus plummeting down. "We have recovered 39 dead bodies. DNA tests will be carried out for identification of the dead," Hamza Anjum, a senior district official, said. Anjum said the bus had been speeding when it hit the pillar and careen into a ravine. The bus also caught fire, he said. Another four people were rescued and taken to a nearby hospital. The death toll is expected to rise since many of those injured were in critical condition. Road accidents are common in Pakistan due to a lack of infrastructure, poorly maintained vehicles and careless driving.