CHANGSHA - The six miners who have been missing since a coal mine accident in Central China's Hunan province on May 2 are considered dead and rescue work has stopped, local authorities said Saturday.

The miners with the Congshan Coal Mine in the township of Shashi in Shaodong county went missing after their cage plunged into the shaft at about 8:45 pm on May 2, according to county officials.

Rescue efforts were temporarily suspended on May 8 after rescuers were sent 165 meters underground. At that depth, toxic gases, such as hydrogen sulfide and carbon dioxide, exceeded safety limits, according to the provincial Coal Mine Safety Bureau.

The toxic gas concentration forced rescue efforts to finally end on May 9. Experts at the site believed that there was no chance the missing miners could have survived, judging from the toxic gas concentration in the shaft and the rotting smell of their remains.

County government officials have sent their condolences to the families of the deceased.