The number of workers known to have been trapped by a coal mine flood earlier this week was raised to 16 Friday, after it emerged that one miner failed to sign the attendance book before entering the shaft, a senior work safety official said.

Wang Heshou, vice director with the State Coal Mining Safety Supervision Administration, also told reporters at the site of the accident in Guizhou Province that the flood occurred at 8 a.m. Wednesday, instead of 3:30 p.m. as earlier reported by the county government.

Wang Lin, head of Qinglong County, where the accident took place, claimed Friday evening that his office got the time from the county's public security bureau, which had questioned witnesses.

Wang Heshou pledged that the cause of the time difference would be strictly investigated.

Rescuers were still trying to find the miners, despite difficulties in pumping water out of the substandard mine. They have maintained power and ventilation supply through the shaft in hopes that the trapped workers could survive until they were rescued.

Ma Lian, an engineer with the provincial work safety department, said the mine was under renovation to expand production from 30,000 tonnes to 150,000 tonnes. However, the owner had not made sufficient investment to guarantee safety.

"The mine sap is narrow, and the mining facilities are outdated, which also caused difficulties for rescuers to bring machinery into the mine to aid the rescue," he said.

The mine owner was blamed for failing to report the accident in time, which meant that the optimal time for rescue had passed.

(Xinhua News Agency June 19, 2009)