Two men were injured when a speedboat, hired by the navy to intercept unauthorised vessels on the Hooghly, caught fire on Tuesday morning.

The injured are civilians who were preparing the boat, docked at Babughat, for a patrol when the fire broke out around 7am, an officer said. There were no navy personnel on board.

Some naval officers and sailors on another boat nearby alerted the fire brigade. Two fire tenders reached the boat within minutes and doused the flames in an hour.

"Of the two fast interceptor boats (FIBs), one caught fire. It's too early to say anything, but primarily it appears a short circuit triggered the fire. The presence of fuel turned it into a blaze in no time," the naval officer said.