At least 29 people were killed when a truck loaded with explosives blew up on a mainland highway yesterday, destroying a bus carrying passengers from Shenzhen. The accident happened at about 4am near the city of Shangrao in Jiangxi . The blast was felt several kilometres away. The victims all died at the scene. Seven villagers living nearby were injured, including a pregnant woman, while nearly 60 village houses were damaged, Xinhua reported. It was not known last night if any Hong Kong residents were on the bus, which left Baoan in Shenzhen on Wednesday and had been due to arrive in Quzhou in Zhejiang yesterday. Authorities said the blast was caused by a collision between the truck, carrying fireworks explosives, and a third vehicle. Witnesses said all three vehicles were destroyed by the blast. A shopkeeper living 2km from the scene said: 'I was woken up by a huge blast. It was followed by another big explosion. I got up and looked outside. It was raining so I thought it was thunder.' The Jiangxi government sent 500 police to the scene and the injured were taken to a hospital in Shangrao. A nurse at the hospital said most of the seven injured villagers, who were all in serious condition, suffered broken bones and head injuries. A spokeswoman for the Quzhou Changyun Bus Company in Quzhou confirmed the bus was owned by the company. She said there were about 30 people on the bus, including the driver and ticket seller. 'Most of the passengers are local people. Generally, we don't have foreign or Hong Kong passengers.' Some of the victims' families had gone to the company's office to find out more about the accident, the spokeswoman said. The truck was transporting fireworks ingredients from Hunan to a factory in Zhejiang.