Tuesday's devastating fire in a multi-storeyed building here on Park Street, which has so far claimed 24 lives, is an eye-opener to the existence of illegal constructions in the city behind which there is a “racket” working in connivance with a section of the civic administration, Chief Minister Buddhadeb Bhattacharjee said here on Thursday.

Even as the city struggled to come to terms with the tragedy at Stephen Court, Mr. Bhattacharjee called for stern action against those behind such unauthorised constructions and who flouted the prescribed building rules.

“There is need to intervene in such situations wherever they may occur to prevent tragedies like this,” the Chief Minister told the Assembly.

Cautioning the concerned authorities — the Kolkata Municipal Corporation (KMC) and the State's Urban Development Department — against such unauthorised constructions, Mr. Bhattacharjee said: “I cannot allow such a situation. We must take action wherever such constructions exist.”

Exemplary punishment will be meted out to those found guilty of flouting building rules and setting up unauthorised structures, he added.

What Mr. Bhattacharjee found intriguing was how the two top floors of Stephen Court, which were illegal constructions, could have been allowed to come up by the local civic body — the KMC — which had the floors regularised subsequently.

The KMC's role at the time is being inquired into and stern action will be taken against those responsible. “How and when such an approval was given will have to be ascertained,” he said.

On the on-going operations at the building, which he visited on Wednesday, Mr. Bhattacharjee said the thrust was on clearing the rubble at the site and ensuring the treatment of those injured, for which the State government will bear the cost.

The government already announced a compensation of Rs. 2 lakh to the next of kin of each victim of the tragedy.

It could not be said for certain that there were no more bodies in the building as search operations were on, Mr. Bhattacharjee said.