LORRY drivers returning to Hong Kong from Shenzhen told of being rocked by the blasts as they made their way back to the territory. Chin Ying-lam, 40, was heading back to Hong Kong along Lei Kwong Road near Qingshuihe when his lorry was shaken. ''The explosion shook my 40-foot-long container. When I looked around I saw a huge column of smoke in the shape of a huge mushroom billowing up in the sky,'' Mr Chin, 40, said. Until he saw the column of smoke, he thought there had been an explosion in the nearby government dangerous goods depot, which covers an area as large as the Fanling industrial area. Mr Chin said that when he arrived at the Man Kam To border checkpoint he was asked by Chinese customs and police officers whether he had heard or seen the explosion. He said they had no news of what had happened or where the explosions had occurred and wanted to obtain some information from him. Another Hong Kong driver, a 32-year-old who identified himself only as Mr Man, said he had heard a huge explosion while driving near Buji towards the border. He looked up and saw a column of smoke like a large black mushroom in the sky and thick dark dust falling. Shortly afterwards, police stopped his lorry and directed him along another road because the one he was on had been closed to traffic. ''There were many police vehicles, ambulances and fire appliances speeding along the road, which could only be used by essential services,'' Mr Man said. He said after his vehicle was diverted he had difficulty finding another road to get to the Hong Kong border. ''It look me a long time and much circulating before getting there,'' he said. Residents living in Lok Ma Chau, close to the Sino-Hong Kong border, said they heard several explosions. The blasts rocked buildings and furniture and shattered glass. One man in Shenzhen said he had helped rescue some of the survivors after hearing the first explosion. ''When I arrived at the scene, some of the warehouses were still on fire,'' he said. ''Fire was coming out of a broken gas pipe on the ground.'' There was a strong smell of ammonia, he said, and he put on a mask. Police fighting the fire were also wearing masks or wet towels to keep out the gas. ''I saw them carrying barrels of chemical material from warehouses which were not yet burnt. ''The warehouses were built from iron sheets, and sophisticated fire prevention facilities there would not be available,'' he said. Firemen standing on top of fire engines were thrown into the air by one blast. The witness saw two construction workers lying in an ambulance. ''I guessed that they were dead, because their heads [were] down, but their hands could still hang up in the air without any support,'' the man said. Many cars parked near the warehouses were seriously damaged. A China-made ''Red Flag'' limousine, specially designed for Chinese leaders, stood undamaged about 100 metres from the scene. Residents of an estate 400 metres away were not allowed to return to their homes last night.