It was all, as if, written on the wall – the massive Ta Po killer fire.

On Nov 20 – just six days before the deadly blaze ravaged Wang Fuk Court in Ta Po, Labour Department officials had issued a stern written warning to the contractor following an inspection of the eight-block residential complex, reminding it of the importance of fire safety.

“It was because one of the complaints received was about workers smoking on the site,” Secretary for Labour and Welfare Chris Sun Yuk-han said on Saturday, referring to the renovation work going on at the estate.

He said the department had taken the precautionary measure of warning the contractor in response to a related media query after a radio program.

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According to Sun, the department had conducted six rounds of inspections at the complex since July last year and issued six improvement notices.

It made three prosecutions, mainly concerning the safety of workers, he added.

“Our major concern then was the safety of working at a height. During the inspections, the department had also given a written warning to the contractor concerning the importance of fire safety,” Sun said.

The inferno, which started at 2:51 pm on Wednesday and was finally put out at 10:18 am on Friday, has so far claimed 128 lives, with 150 people still unaccounted for.

Secretary for Security Chris Tang Ping-keung said on Friday the blaze is believed to have originated on the lower-floor mesh netting of Wang Cheong House – one of the seven charred buildings at the estate – and spread rapidly due to the highly flammable styrofoam attached to the windows.

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The cause of the fire has yet to be determined, he said, adding that a police investigation is expected to take three to four weeks.