Three fire engines were rushed to the Five Gardens area of Matunga in central Mumbai as a gas smell filled the area on Saturday morning, officials said.
The fire brigade officials were suspecting a gas leak.
"We are suspecting a leak from the gas pipeline in the area, but have not been able to ascertain the exact cause and source of the leak," an official said.
The odour spread in nearby areas in the four-km radius, before it evaporated, the official said.
No deaths or injuries have been reported in the incident so far.