A Hong Kong family's annual tomb-sweeping trip to Huizhou ended in tragedy yesterday when five members were killed in a car crash. The accident happened at about 1.30am, when the Mercedes-Benz the family was travelling in collided head-on with a truck on a section of National Highway 205 in Boluo. Hong Kong men Chow Wing-fai, 37, a car repair shop owner, and Chow Kam-lung, 40, a truck driver, were killed instantly, along with three mainland relatives, Wang Jianhui, Zou Shilin and Zou Shiwen , who was driving the car. The mainlanders were all aged 32. Two other passengers were injured - Hong Kong resident Chow Fook-lai, 56, a factory owner, and another mainland relative, Zou Biwen, 27. They were transferred from a Boluo hospital to the Huikang Hospital in Huizhou for treatment yesterday morning. The three occupants of the truck were not hurt. The family set off for the trip shortly after midnight, after a late dinner in Huizhou. Boluo police said the truck driver had been driving on a rerouted lane because of some roadworks, but had allegedly failed to switch back to the proper lane after the repair section ended. Xinhua also quoted the Boluo police as saying the accident could have been caused by unclear road signs. The driver has been arrested for further investigation. Yesterday afternoon, fruit scattered from the truck during the collision could still be seen at the scene of the accident. Chow Fook-lai was in a stable condition in the intensive care unit last night. 'He broke 11 ribs on the left side of his chest and five on the right. His condition is stable but his injuries are very serious. It will take at least two weeks to know the full extent of the damage,' said Dai Bin, a doctor at the hospital. Zou Biwen suffered head and chest injuries. Two Hong Kong immigration officers arrived in Huizhou last night to assist the family. Senior immigration inspector Leung Chiu-pun said Mr Chow was still in a critical condition and unfit to travel. She added that the government would keep in close contact with the family and offer assistance whenever possible.