Kolkata, June 25 (IANS) The roof collapse in the under-construction warehouse in the Taratala area of Kolkata was due to faulty construction, low-quality materials, and wrong planning.

These points have been highlighted by the Kolkata Municipal Corporation in a report submitted to the Commissioner of KMC on Thursday.

According to the report, the construction design was approved on the 54-katha land in February 2025, following which a three-storey structure was built there. According to the rules, iron casting has to be done from the first floor. But in the warehouse case, the casting work was started from the third floor. The construction structure could not bear that load.

The report said the material used for casting was of low quality.

The three-storey structure was erected without strengthening the base and the lower side, which led to the disaster on Thursday afternoon.

The report also said that this construction design was approved for 43 out of 54 kathas of land.

Following the disaster, the investigation has thus far found that construction activities were taking place on an extra five kathas of land, exceeding the sanctioned design. The builders had unlawfully expanded the warehouse dimensions.

The report submitted by the building department said that there was no error in the original construction design. But there was negligence in supervision by the concerned officials and those involved in the construction.

The building department has mentioned in the report that due to a lack of sufficient staff, supervision of work is affected in such constructions.

Nine workers were killed, and 20 others were injured after the roof of the under-construction warehouse collapsed in Taratala. The injured have been admitted to the SSKM Hospital for treatment. The condition of the two is said to be critical.

So far, five people have been arrested in the warehouse collapse incident. The police have lodged a suo motu FIR under various sections of the Bharatiya Nyaya Sanhita (BNS), including culpable homicide and attempt to commit culpable homicide.

The Kolkata Police have also formed a Special Investigation Team (SIT) to probe the incident.

–IANS

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