An unidentified man fired a round from pistol outside a medical shop in suburban Malad on Saturday afternoon, the police said.
Nobody was injured in the incident which took place outside Anand Medical Store in Shivaji Nagar area of Kurar village, said an official.
The man fled from the spot after firing the shot, he said.
Senior police officials rushed to the spot, he said, adding that it was being probed if it was an attempt to threaten the shop owner.