Engineers are working on an alternative rescue plan for the 33 miners trapped underground in Chile that could dramatically speed up the rescue process.
They are looking at broadening an existing shaft some 12cm in diameter about 300 metres from an emergency shelter where the miners have been living in hot dank conditions 700 metres below the surface since 5 August.
The trapped men, who were discovered alive on 22 August, were told on Wednesday that it could take up to four months to rescue them by means of a 700m vertical tunnel drilled by a special hydraulic bore.
The BBC reports drilling could begin as early as Sunday.
With five of the men showing signs of depression, the American space agency NASA is sending a team of experts to Chile to advise on the nutritional and behavioural effects of being stuck underground for so long.