Fire officials are probing the cause of the blaze in the Indian financial capital which erupted on Saturday night on the 14th floor of the 21-story tower block, officials said.

“We have confirmation of seven deaths. At least 25 others are injured and are undergoing treatment in various hospitals,” an officer in the Mumbai fire department’s control room told AFP.

At least three people died after they tried to use the lifts to flee the fire which some officials have blamed on an electrical fault in an air-conditioning unit, according to local media reports.

“We rescued five persons of the same family from one of the gutted flats. Over 20 persons from the building were rescued safely,” senior fire officer P.S. Rahangdale told the Hindustan Times daily.

The incident comes barely a month after four senior officers of a Mumbai fire brigade died in a blaze at another building.

Mumbai has also suffered from a string of building collapses including one in April 2013 that killed 74 people.

Those incidents highlighted poor construction methods and substandard materials and violations of building codes as a result of a huge demand for housing in the city.