Karnataka Director General of Police (chief of fire and emergency services) M N Reddi on Wednesday said that the death toll in the under-construction building which collapsed at Dharwad on Tuesday jumped to seven as rescuers pulled out four more bodies from the rubble of the collapsed four-storyet building. He added that one person who got seriously injured in the accident passed away at the hospital.

Talking to PTI, Reddu said that 55 people have been pulled out from the debris of the collapsed building. Earlier, Hubballi-Dharwad commissioner of police M N Nagaraj had also said that 55 people had been rescued. Nagaraj added that the police were yet to arrest anyone in connection with this accident.

"We have registered a case. Arrests will also follow but our focus at present is on the rescue operations," he added.

Police said rescuers are working tirelessly to extricate people who are still feared trapped beneath the debris of the collapsed building.

A total of 10 ambulances and five fire tenders are taking care of relief and rescue operations with three teams of the National Disaster Relief Force (NDRF).

"Two more teams of #NDRF are being airlifted from Ghaziabad in addition to one team which was moved from Bangalore in connection with Dharwad building collapse," the NDRF tweeted earlier in the day.

Police, fire and emergency personnel are also helping the NDRF teams in relief and rescue operations.

An eye-witness told PTI that the building did not have the capacity to bear four storeys and it collapsed like a heap of cards when the owners decided to add an extra floor. "The builders had used substandard materials," he said. Sources said that majority of the victims were migrant labourers from north India.