Two labourers died and three others were rescued after a three-storey house that was undergoing renovation collapsed in south Delhi's Satya Niketan area on Monday, police said.
Another labourer, who was outside the dilapidated building at the time of the incident, had a narrow escape, they said, adding that an FIR has been registered in the matter.
The South Delhi Municipal Corporation (SDMC) also announced a probe into the incident.
Around 1.25 pm, a PCR call was received at the South Campus police station about the building collapse in Satya Niketan, the police said.
Deputy Commissioner of Police (Southwest) Manoj C said, "One labourer who was outside the building had a narrow escape. He sustained injuries and was admitted to a hospital for treatment."
"Southwest district police with assistance from Delhi Fire Services and NDRF began the rescue operation at the spot and rescued all the five trapped labourers," he said.
Two labourers died later and the remaining four are undergoing treatment, he said.
"An FIR has been registered in the matter," the DCP said.
The deceased have been identified as Bilal and Naseem and the injured as Md Firdaus, Aslam, Sarfaraz and Musahid, the police said.
The rescue operation lasted for over three hours.
Earlier, Director of Delhi Fire Services Atul Garg said, "We received a call around 1:24 pm about a house collapse in Satya Niketan building number 173 here. Six fire tenders have been rushed to the spot."
Since this building was in a congested area, the main challenge was to take the rescue vehicles inside. It was a difficult task, he said.
All the five labourers who were trapped under the debris have been rescued and rushed to a hospital for treatment. The rescue operation has ended, Garg said.
The National Disaster Response Force (NDRF) pressed its sniffer dogs into service to search for survivors and used drilling equipment and cutters.
An NDRF personnel said the labourers got trapped in the kitchen area of the house.
A senior fire official said according to a preliminary inquiry, it seems that the building was not in a good condition to undergo renovation.
"This was an old building and it was not in a good condition to undergo renovation. We found out through local inquiry that the said building was being renovated to convert it into a PG accommodation. So, they must have broken some structure for this purpose which led to the collapse," he said.
"Since the renovation was underway, no one was living in the building. It has also been found that there was no proper building plan. It was not a planned construction and was also not approved by the concerned authorities," he said.
SDMC Mayor Mukesh Suryan said the civic body will launch a probe into the building collapse.
A notice was served last month to the building owner for carrying out renovation work in the building. On April 11, the Delhi Police was requested to stop the renovation, he said.
Chief Minister Arvind Kejriwal termed the incident "very sad".
"This accident (building collapse) is very sad. The district administration is engaged in relief and rescue work. I myself am taking every information related to the incident," he tweeted in Hindi.
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