"At present, we don't suspect any foul play, but we are investigating the matter," said BR Gite, inspector, Mahim police station.
Eight fire engines, six water tankers and two ambulances rushed to combat the blaze, and managed to control it after five hours. Narrow lanes in the congested slum affected rescue operations, said fire officials.
Locals claimed that four LPG cylinders burst, further adding to the magnitude of the fire.
The injured were taken to Bhabha and Sion hospitals. "The bodies are charred beyond recognition. We can't even distinguish the gender," said Dr Pradeep Jadhav, medical superintendent, Bhabha Hospital. The Mahim police have registered a case of accidental death.