At least seven labourers were killed and one was seriously injured when they fell to the ground while working inside an elevator shaft at an under-construction building in Ahmedabad city of western Indian state of Gujarat today, police said.

Police had earlier put the death toll at eight, but an official later said one worker was undergoing treatment, reports our New Delhi correspondent.

The incident took place at the site located near Gujarat University.

A senior police official had initially said the elevator carrying the workers had crashed to the ground from the seventh floor but later police said the workers fell when the structure inside the elevator shaft gave way.

"Six labourers who were working inside the elevator shaft on the 13th floor fell to the ground after the support structure suddenly collapsed," said Assistant Commissioner of Police LB Zala.

"Two others who were working on the fifth floor also fell down after losing balance. Seven of them died while one is undergoing treatment," he added.

Preliminary probe show necessary safety measures were not in place and appropriate action will be taken if any negligence is found on the part of the contractor, the ACP said adding the labourers were not wearing any safety gear.

Ahmedabad Mayor Kirit Parmar said police will take necessary action against the builders if they are found to have violated any laws.