Rescuers were seen using their hands to dig up the ground and retrieve bodies, local television showed, and authorities said more victims could be trapped inside the debris. Rescuers were also shown carrying the injured through narrow lanes on makeshift stretchers.
Within the last 24 hours authorities have so far reported 11 incidents of houses or walls collapsing in the Mumbai area, officials said.
In one neighbourhood about half a dozen shacks located at the base of a hill collapsed on top of each other, officials said.