Ben Marriott's boat – the O-B-One, a 17ft D John vessel – was broken into on Sunday and, after the culprits had taken the boat for a "joyride", they stole its fuel packs and trashed it, causing damage totalling around £1,000.

Mr Marriott told the Evening News that there had been regular incidents of vandalism and break-ins since April and the harbour authorities had done nothing to combat them.

He said: "There have been quite a few boats broken into recently. They frequently get taken out for a ride by yobbos and it costs their owners thousands of pounds in damages."

He says that he has complained to harbour security about the lack of supervision but feels their response has been inadequate. "They tell you that they'll check the CCTV coverage and that's about as far as you get with them.

"We're supposed to have 24-hour cover there – each of us pays £300 a year for our berths – but whether the security guards actually ever get out of their watchtower is debatable. You do expect to see them making their rounds from time to time, but you never do."

Mr Marriott added that, until this year, his concerns about security at Scarborough harbour had been so strong that he refused to moor a boat there – even though he lives in town himself.

"This is the first time I've berthed a boat in Scarborough," he added. "I've had two or three boats over the years but I was always too concerned to leave them in the harbour. In April I thought I'd give it a go – looks like I made the wrong decision.

"I should have seen the warning signs. A couple of insurance firms told me they'd only give me third-party cover for the boat if I berthed it at Scarbor-ough."

As well as removing his boat's fuel packs, the hooligans also ripped the boats seating out, as well as leaving it covered in empty beer cans.

"It was just wilful damage," Mr Marriot said. "I'm going to have to take the boat out of the harbour for repairs and I don't know how much work will be needed. It's a £4,000 boat and it could be a write-off."

However, Scarbor-ough Council defended the harbour's security record.

John Riby, head of technical services, said: "I would like to reassure harbour users and the general public that events like this are not a common occurrence. However, due to the number of boats in the harbour at any one time, including visiting crafts and the number of people coming and going from the harbour at all different times of the day and night, we cannot guarantee 100 per cent security.

"When unfortunate incidents do occur, such as the case at the weekend, we do everything in our power to assist the police in their criminal investigations, including evidence from our duty watch keeper and our CCTV centre which monitors the harbour area. Only last week, the evidence collected by our CCTV team was successfully used by the police in connection with a criminal incident on the harbour walls.