The cylinder blast triggered a fire and the walls of the house in which the blast took place and another opposite it collapsed under the impact of the explosion, senior district administration official said.
Seven fire tenders were rushed to the spot after the incident which took place around 8 PM, a Fire Brigade official said.
The deceased were identified as Rajesh Goyal, Poonam and Soni Ram, all family members. The injured were Naina (4), Girish (6), Krish (12), Naushad (8), Sonu Kashyap (60), Ahmad and Abbas. The other injured persons are yet to be identified, police said.
Another cylinder blast incident was reported at south east Delhi's Ashram area around half an hour later.
"Several persons are feared injured in the fire incident which occurred in a house following a cylinder blast. Rescue operation is going on," a senior district administration official said.
Fire department official said that the incident was reported around 8.30 pm and several fire tenders were rushed to the spot.