The packed bus of Kalyan Dombivili Municipal Transport, heading from Malangh Gadh to Kalyan caught fire at around 9 PM yesterday, district authorities said.
One of the passengers alerted the bus driver, Dileep Pardeshi, saying that he could smell something burning.
The driver immediately stopped the bus at a road side near the Sanai Mangal Karyalaya in Bail Bazar and evacuated it quickly.
It was later found that a short-circuit in the battery resulted in the fire, which reduced the bus to ashes within minutes, sources added.