Wellington's Bluebridge ferry says what appears to be a vessel on fire in the harbour is part of a drill.
A witness says the ferry came into the harbour early on Saturday morning and emitted a series of hoots, then carried out a 180 degree turn and appears to have let out some smoke.
However, the Fire Service and Bluebridge Ferries say the manouevre is part of a routine drill and is nothing to be alarmed about.
The smoke has come from a smaller vessel next to the ferry.