Five specialists Tuesday arrived at the gas blast site of the Chenjiashan Coalmine in northwest China's Shaanxi Province to help the rescue and investigation work.

The five specialists were appointed by the State Administrationof Work Safety. They will provide know-hows in ventilation, coalmine gas, fire control and electric system, according to sources with the administration.

By Tuesday morning, remains of 63 victims of the explosion accident had been found, with another 103 miners still trapped underground, said Huo Shichang, head of the provincial coal industry administration.

At 7:20 Sunday morning, 293 miners were working underground when the gas explosion happened at coal pits some 8,000 meters away from the tunnel entrance. A total of 127 miners, who worked mostly near the entrance, were rescued.

The coal mine is a high-gas-density colliery, featuring intergrowth of coal, oil and gas. Its coal bed remains responsive to fires. The mine used to suffer a fire every three to six months,and the shortest break between two fires was 24 days. The Sunday explosion devastated all ventilation systems underground, with a great deal of harmful gas bursting out. The main ventilation system resumed operation on Monday. According to preliminary analysis, there still exists flaming areas underground, exposing the mine to a new accident and threatening the ongoing rescue work.