Twelve persons were rescued from under the debris and rushed to hospitals, police said.
While three persons were brought dead at Bara Hindu Rao Hospital, one person was brought dead at Acharya Bhikshu Hospital.
"Five persons were brought to our hospital out of which three were brought dead. Two others were injured and they are being treated," said Dr R B Mittal, Medical Superintendent, Bara Hindu Rao Hospital.
According to fire officials, they got a call around 9 AM about a building collapsing at Tulsi Nagar in Inderlok following which four fire tenders were rushed to the spot for
the rescue operations.
The incident took place in a congested locality and seems to have been caused by construction work on an adjacent plot, a fire official said.
"The building was around 50 year old and a number of families lived there," said Deputy Commissioner of Police (North) Madhur Verma.