New Delhi

A multi-storey residential building collapsed in northeast Delhi's Shakti Vihar area in the early hours of Saturday, leaving 11 people dead and 11 injured, officials said.

Teams of the National Disaster Response Force (NDRF), fire services, Delhi Police and other volunteers carried out rescue efforts for over 12 hours at the site of the 20-year-old four-storey structure that collapsed in the Mustafabad area of the national capital around 3 am.

A police source said construction work in "two-three shops" on the ground floor could have led to the collapse.

Delhi Chief Minister Rekha Gupta ordered a probe into the incident and expressed sadness over the incident.

Locals said construction work going on at a new shop could have triggered the collapse. They also expressed concern about the fragile state of four to five buildings.

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Waste water from the sewer has been seeping into the walls of the buildings for years, and over time, the moisture has weakened the structure, causing the walls to develop cracks," said Salim Ali, another resident.

The Municipal Corporation of Delhi, in a statement, said that the structure was around 20 years old and was fully occupied.