The structure, located on Western Marg in the Saidulajab area, was reduced to a huge mound of rubble, with broken concrete slabs, twisted metal and shattered pillars scattered across the site.

Officials said a multi-agency search operation was continuing amid fears that more people could be trapped under the debris.

"A total of 12 people have been rescued. Two are critically injured. It doesn't look like anyone else is trapped but the search operation is still ongoing," a senior police officer told the media, adding that a case would be registered in connection with the collapse.

Students among those affected

Witnesses described scenes of chaos moments after the building came crashing down around 7.45 pm.

The building housed coaching institutes, cafes and offices, while construction work was reportedly underway on the third floor.

Fire officials said the ground-plus-three-floor structure collapsed completely, crushing an adjoining tin-shed canteen where students were having dinner.

Many of those present were medical aspirants attending coaching classes in the area.

Neelam had recently returned from abroad after completing her MBBS and was preparing for postgraduate entrance examinations at Arise Medical Academy in Saket.

Massive rescue operation

According to Delhi Fire Services (DFS), three people were rescued by local residents and police personnel before firefighters arrived. Additional survivors were later pulled out by rescue teams with assistance from the National Disaster Response Force (NDRF).

As the scale of the disaster became clear, additional fire engines and specialised rescue equipment were rushed to the site.

Firefighters, NDRF personnel, Delhi Police, district authorities and local residents worked together to search the debris.

Heavy machinery, including JCB excavators, hydraulic cutters and jacks, was deployed to remove concrete and steel. Rescue teams also used victim-location cameras, earth-auger drilling machines and trained sniffer dogs.

Visuals from the site showed anxious relatives, residents and students gathered around the rubble as rescue efforts continued under floodlights.

Fears of more people trapped

Residents said the building was frequently used by students and office-goers, raising concerns that more people could be trapped.

Some locals estimated that as many as 100 to 150 people may have been in or around the building at the time of the collapse.

Dharamveer Singh, an official from the district magistrate's office, said rescue personnel were continuing efforts to reach anyone still trapped beneath the debris.

Ravinder Singh, president of the Chaar Gaon Committee, said many of those feared trapped could be students attending coaching institutes in the area.

Investigation into collapse ordered

Police said an investigation would examine ownership of the building, construction permissions and whether any violations or lapses contributed to the collapse.

Deputy Commissioner of Police (South) Anant Mittal said the police received information about the incident at around 7.35 pm and rushed personnel from the Mehrauli police station to the site.

"We have been informed that the premises were being used as a canteen for medical students and some people may be trapped. Rescue operations are being jointly carried out by the NDRF, DDMA, fire services and Delhi Police," he told the media.

Officials said the full extent of casualties and damage will only become clear after rescue operations are completed and everyone inside the building is accounted for.