An apartment block collapsed in the Indian financial hub Mumbai on Friday, killing six people and injuring three others in the latest of a string of deadly building cave-ins, authorities said.
Dozens of rescuers scoured the rubble in search of anyone still trapped under the flattened remains of the seven-storey building, located in a densely populated area of the city and surrounded by other structures which were hit with debris.
"There have been six deaths, of which we can confirm two are women. Three persons have also been injured," a municipal official told AFP, asking not to be named.
Searchers, including fire brigade and police officials, worked through the evening at the site in a Mumbai suburb.
Rescuers using heavy digging equipment waded through twisted steel and concrete rubble from the building to see if there were other victims while residents stood around watching.
"We do not yet know the exact number of people who might be trapped," the municipal official said.
One official from India's emergency response agency said however that he believed the toll of dead and injured would not increase significantly.
"Information indicates two families were caught in the collapse so we are hoping the numbers will not rise sharply from here," Commandant Alok Avasthy of the National Disaster Response Force told AFP.
Avasthy promised that rescuers would stay at the site until all potential victims were pulled out.
"Two teams from National Disaster Response Force, amounting to 65 personnel, are on the spot and will continue the operation until we are sure everything is clear," he said.
Police initially thought no-one was in the building as it had been cleared of tenants after being declared uninhabitable by municipal authorities who had served a demolition notice.
But in teeming Mumbai, where housing is in huge demand and extremely costly, the demolition order had been challenged by the tenants, area residents said.
Local media reported that a court had stayed the demolition order and that some people had been living on lower floors of the building which collapsed.
The building was served a demolition notice in 2007, 2008 and 2010, a senior municipal corporation official was quoted as saying by the Press Trust of India news agency.
"However, the matter was taken to court and the demolition was stayed," the official said.
Mumbai's mayor Sunil Prabhu said tighter law enforcement could avert such events.
"This tragedy could have been avoided. We need laws that give more powers to the municipal corporation for acting in time against such structures," Prabhu told NDTV.
Building cave-ins are a relatively common occurrence in India where a fast-growing population makes housing a sought-after commodity.
Substandard materials, lax building code enforcement and shoddy building standards -- combined with rampant corruption -- often lead to poor quality housing.
Last September, a rundown residential block in Mumbai collapsed, killing 60 people.
And in April last year an illegally built building caved in on the outskirts of the city, killing 74.