Four people died and two others were injured in a collision involving a car and a private bus on National Highway 40 here in Nandyal district, the police said on Friday. The accident occurred late on Thursday night when the car was proceeding towards Nandyal at high speed. The driver lost control of the vehicle, hit the road divider, crossed into the oncoming lane and collided with a private bus bound for Arunachalam. “Four persons died on the spot, while two others were shifted to a hospital at Nandyal, where they are undergoing treatment,” Allagadda Deputy Superintendent of Police (DSP) K Pramod Kumar told media reporters. Preliminary investigation suggests that the accident was caused by either overspeeding or driver fatigue. Meanwhile, all passengers in the private bus were shifted to another bus and no injuries were reported, he added.