A loose manhole cover near the Siddharth College junction struck the undergear high-voltage battery of a Switch-class air-conditioned double-decker electric bus, triggering a fire and thick smoke around 9.15 am during rush hour on Tuesday.

This journalist witnessed the incident and saw passengers evacuate the bus immediately as dense smoke began to engulf it amid heavy rain. Most passengers were accommodated in the next bus operating on the same route.

Fire brigade personnel rushed to the spot