Thirteen rescuers, including six divers, had entered a flooded mine in north China's Shanxi Province to search for 153 miners that had been trapped for a week, rescue headquarters said Saturday afternoon.

The team of rescuers were sent down to explore the flooded shaft in the Wangjialing Coal Mine, Xiangning County at 1 p.m. to prepare for a large scale operation, said a spokesman with the headquarters.

The divers were carrying underwater cameras to film the environment in the shaft, he said.

Early Sunday morning was the soonest timing when a large-scale rescue operation could be launched, he added.

A total of 283 rescuers are in the mission, while 158 ambulances, one for each trapped miner, are standing by with 156 medical staff to ensure immediate treatment once the trapped miners are rescued.

Water level in the mine has dropped by 5.3 meters since the flooding happened. Rescuers are draining 2,000 cubic meters of water per hour.

Rescuers said they heard the trapped miners banging on a metal pipe at 2:15 p.m. Friday.

An iron wire was found attached at the end of a drill pipe, which was used to pump out water and send down food, when it was lifted to the surface at 3 p.m..

Pan Zengwu, deputy chief of the Shanxi provincial coal geological bureau, said this was apparently tied on by the trapped miners.

The flooding happened at about 1:40 p.m. on March 28 when underground water gushed into the pit, which was under construction. Altogether 261 miners were working underground at the time, of whom 108 were lifted safely to the surface.

If the trapped workers cannot be saved, the accident will be China's worst mining disaster in more than two years. In August 2007, a total of 181 workers died at two flooded coal mines neighboring each other -- 172 at one mine -- in Xintai, eastern Shandong Province.