NANCHANG - Nine people were injured and three others remain missing after a vehicle carrying explosives blew up at a copper ore mine on Thursday morning in Yongping county, East China's Jiangxi province, local authorities said.??

At about 9:50 am, an explosion occurred while the vehicle was being washed at the copper ore mine affiliated with the Jiangxi Copper Corporation, sources with the provincial government said.

As of 9 pm, the driver of the vehicle and other two workers at the scene remained missing, said Wu Long, director of the mine's publicity department.

The injured have been sent to local hospitals and are in stable condition, Wu added.

An investigation into the explosion is underway.

The provincial government has ordered the copper ore mine to halt production until the cause of the accident is identified, and mines throughout the province have been ordered to suspend the use of the model of vehicle involved in the accident.

The copper ore mine in Yongping covers an area of about 10 square kilometers. It is the country's second largest open pit copper mine.