Arson is suspected in a fire that damaged a North Shore Shark Adventures tour boat — the third this year — and a privately owned vessel parked next to it in Hale­iwa Harbor Thursday night.

Waialua firefighters arrived at 11:42 p.m. to find the cabin and deck of the 35-foot shark tour boat in flames on a trailer in the Hale­iwa Harbor trailer yard. The fire was brought under control five minutes later. Damage is estimated at $100,000.

Heat from the fire also caused $20,000 damage to a 40-foot private boat on an adjacent trailer, Hono­lulu Fire Department spokes­man Capt. Terry Seelig said.

William Aila, Board of Land and Natural Resources chairman, said the fire was an "unfortunate incident."

Aila, who was at the Hale­iwa Boat Harbor yesterday as state crews were surveying tsunami damage to piers, said the two boats were on trailers in the parking lot off Hale­iwa Road.

He said there are no night security patrols at any state boat harbors because of budget cuts.

Aila said there have been no new leads on the previous fires, which happened to boats moored in the harbor.

A fire reported just after midnight Jan. 24 caused an estimated $225,000 damage to the cabin and front end of the 30-foot North Shore Shark Adventures tour boat Kai­lolo.

The 30-foot North Shore Shark Adventures tour boat Kolohe burned in a 12:30 a.m. fire Jan. 7. Damage was also estimated at $225,000.

Investigators determined the January fires were also deliberately set.

Seelig said the investigation has been turned over to Hono­lulu police. He said anyone with information is asked to call police or Crime­Stop­pers.

Aila said North Shore Shark Adventures planned to replace the two boats that had been damaged in January.

Joe Pavsek, owner of North Shore Shark Adventures, was on Lanai yesterday and unavailable for comment.

Besides North Shore Shark Adventures, Hawaii Shark Encounters also offers shark tours out of Hale­iwa Harbor.

The business has been controversial because of the practice of feeding sharks to attract them.

Feeding sharks is illegal in state waters within three miles of shore.

Five shark tour workers from both companies were arrested last year for feeding sharks within the three-mile limit, but a state judge threw out the charges in January just before the case went to trial.

Opponents of shark feeding say the practice attracts sharks, hurts fisheries and is disrespectful to native Hawaiians who believe sharks are ama­kua, or ancestral gods.

But shark tour operators say they only venture into areas where sharks are already pres­ent. They say sharks have congregated in the area off the North Shore since the 1960s, when crabbing boats used to throw out old bait into the ocean from their traps.

Mahina Chillingworth of Hui o Hee Nalu, a North Shore group of surfers and other community members opposed to shark feeding, said, "We’re beyond surprise or disbelief" to hear that more boats have been set ablaze on purpose. She said this is something her organization would never condone.

"The hui has never been anti-business," she added. "That’s not pono. That’s not the local way."