The two men were killed in Bhandup suburb of north-east Mumbai.
The incident occurred when the retaining wall of the shopping complex near Kajutekdi collapsed following torrential pre-monsoon rains which lashed the city and suburbs through the day on Friday.
Police said that four young men were standing near the wall, which suddenly fell and trapped them under the debris.
Ravindra Ghanekar, 35, was taken to a hospital in Mulund, where he was declared dead. The body of Rahul Gaekwad, 22, was recovered by rescue workers Saturday morning from the debris.
Two others injured in the incident, Sunil Jadhav and Manik Jadhav, are under treatment at a Mulund hospital.
In the past five days, six people have died because of pre-monsoon rains in Mumbai, Thane and Pune.
One woman was killed and another went missing Thursday after a landslide was triggered by torrential rains near Shindewadi on the Pune-Satara road in Pune district.
Several vehicles were damaged or washed away as flash floods engulfed the road.
Two farm labourers died on Monday after being struck by lightning during a thunderstorm in Thane district.
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