"It's a massive accident, we have retrieved 20 bodies so far, dozens are trapped, we are striving hard to pull out the survivors, if any, from the wreckage," said Ratanlal Dangi, district superintendent of police.
Near and dear ones of those trapped waited breathlessly to know the fate of their loved ones.
Gannon Dunkerley and Company Ltd (GDCL) employed the workers.
The chimney being built for a 1,200 MW coal-fired power plant of Balco would have reached 275-metre height on completion.
The workers protested against the Balco management and GDCL. But the police assurance of strict action against Balco cooled things.
Chief Minister Raman Singh, ordered a judicial probe into the tragedy, and asked the police to register an FIR against the Balco management for negligence.