The makeshift shelters were set up for labourers working for an under-construction residential project located downward where excavation work was underway.
The incident took place between 1:30 am and 1:45 am, police said.
On the probable cause behind the incident, Pune Municipal Corporation commissioner Saurabh Rao said prima facie, the soil may have loosened due to heavy rain coupled with the excavation work that was carried out "irresponsibly" close to the retaining wall of the housing society.
The intensity of the impact increased as many cars parked along the wall inside the society too fell on the shanties, officials said.
Pune had received 73.1