A spectacular fire has broken out at an Auckland marina, destroying at least one boat and damaging five others. 

The fire started in the Pine Harbour Marina at Beachlands at about 3.30pm when a local eyewitness saw flames shooting from a motor yacht and then two men running "hard out" down the pier. 

Russell Heenan, whose home overlooks the marina, said that he thought the men had been working on the boat prior to the fire starting and that it was most likely an accident. 

"A gas bottle just exploded and nearly blew us off the pier," Heenan said. 

Photo / Russell Heenan 

The fire spread to adjacent boats with up to five yachts damaged in the fire. 

"The boat next door to the first one just had about $500,000 spent on it," Heenan said, "The one behind is worth about $200,000 and the original boat, that's now sunk, is worth about $300,000." 

The fire brigade arrived at 3.55pm and quickly had the inferno under control, by which time the original motor yacht had sunk below the water. 

Heenan didn't think anyone was injured in the blaze. 

Photo / Angela Heenan