More than 40 firefighters tackled the incident at Falmouth Docks.

About 200 metres of Queen's Wharf, which was built in 1936, has been destroyed by the fire which broke out at 0230 GMT on Wednesday.

An investigation team from Cornwall Fire Brigade is examining the possible causes of the fire.

The survey ship Tornado was damaged in the fire

At one point, emergency crews used harbour tugs at each side of the wharf to douse the flames, which also caused a wharf crane to topple into the sea.

Only one vessel, the Kingston-registered survey ship Tornado, was damaged during the incident.

The vessel, which had six Russian crew members on board, was towed away from the jetty by the pilot ship LK Mitchell just as flames reached the vessel's gangway.

Five people who were on board were treated for the effects of breathing in smoke.

Falmouth harbour pilot David Barnicoat said: "The flames were fanned by a 25-knot easterly wind.

Firemen fought the fire from tug boats

"There was also debris floating right down the harbour."

Ian Pike, of the dock management company A&P Falmouth, said: "The wharf has been severely damaged to the extent it is no longer usable.

"There are several implications for us, such as we have one less berth for ships to come alongside.

"But all our order books full for all of January."

A visit by the Royal Navy vessel HMS Cornwall, due later this month, has been postponed.