Erroneous tinkering with an arterial support beam and an apparent bid to translocate it could have caused the crumbling of an ageing three-storey building in Palakkad on Wednesday.

Sources said maintenance work was on at the ground floor of the building and a portion of the structure collapsed in a thunderous roar, prompting people inside and on the vicinity to file out immediately.

The debris, comprising mostly of large chunks of concrete, bricks, and tin sheets, were seen right behind a clutter of single-storey ramshackle shops on a street near the busy municipal bus stand.

Read more: Many trapped under debris as building collapses in Palakkad

People in nearby commercial establishments rushed in for the rescue, soon to be joined by the police and the fire and rescue services. After some 20 minutes of the accident, TV crew members reported that there were only earth-movers and no equipment such as concrete cutters to be seen.

A large number of people had gathered at the place, hindering rescue operations. Culture minister AK Balan, the senior-most member of the cabinet after the chief minister, said he had instructed the collector to coordinate rescue efforts. He said any commandeering of equipment or allied services could be done at the minister's level to ensure seamless rescue.

A shopkeeper said a restaurant which functioned out of the ill-fated building had been remaining closed for a while. It was lean hour in the afternoon and the building was sparcely populated.

MB Rajesh, Palakkad MP, said the primary focus was on rescuing those trapped under the debris. Legislator Shafi Parambil said it was heartening that at least 11 people could be rescued.

Rajesh said the old structure could have been weakened in the incessant downpour in the past few days. The ill-conceived repair could have accentuated it.

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