The transformer located on the Ambadi Road in Vasai (west) caught fire at around 10am. The Vasai Virar Municipal Corporation ( VVMC) fire brigade reached the spot. Efforts are on to control the blaze.
Three parked cars and two motorbikes were caught in the flames. Three shops on the footpath near the transformer were also affected.
Fire personnel said that a short circuit could have caused the fire. No casualty was reported.
Traffic on the road was affected in the morning.