Seven persons, including two juveniles, have been detained in connection with the incident, which occurred at around 11 pm on Wednesday at the Khadegolawali locality in Kalyan, they said.
A minor argument escalated into a clash between two groups, during which a member from one side opened fire on the other, an official from Kolsewadi police station said.
A passerby, identified as Rahul Varma, suffered bullet injuries after being caught in the gunfire. He was rushed to a nearby hospital, where he is currently undergoing treatment, the official said.
After being alerted, senior police officials rushed to the spot to bring the situation under control.
The exact reason behind the dispute between the two groups is yet to be ascertained, the official said.
Following the violence, both sides lodged cross-complaints with the police.
"We have so far detained seven persons, including two minors, in connection with the firing incident," the official said.
