Boat owners have hit out at "stupid" pranksters who were caught on CCTV unhooking the moorings of vessels in the city.

Broadsbeat, an arm of Norfolk Constabulary which keeps a watchful eye over the region's waterways, has ramped up patrols after CCTV caught two people unhooking two boats from their moorings alongside the river Wensum in Norwich.

And boatowners have reacted with dismay at the incident, which has also been condemned by the Broads Authority.

Denise Bradley, of Attleborough, owns a Sealine cruiser which is kept in the Brundall marina, but often stays overnight aboard it and moors around Norfolk.

Norwich Evening News: Boatowner Denise Bradley, aboard her cruiserBoatowner Denise Bradley, aboard her cruiser (Image: Denise Bradley)

She said: "It's absolutely terrifying to think people do that. You can't imagine how much of a shock it would be to wake up in the middle of the night and find your boat moving.

"It's such a stupid thing to do and so, so dangerous, particularly in areas where there are strong tides - it can do a lot of damage.

"There was a period a few years ago where it happened a few times - it's worrying to think it happened again. It definitely makes you nervous."

Another boatowner, who moved into a cruiser moored in Norwich just a few days ago, said: "It is obviously very dangerous - it's not something I had really thought about.

"The people who do it probably think it's funny but who knows where the boats could end up if the tide is strong enough - in eight hours you could be in the middle of the sea."

Norwich Evening News: Chris Middleton, who works for The Canoe Man on the Wensum in NorwichChris Middleton, who works for The Canoe Man on the Wensum in Norwich (Image: Archant)

Chris Middleton, 22, who works at The Canoe Man hire company on the Wensum, said he had arrived at work to discover that moorings had been tampered with - although the vessels were doubly secured.

He said: "I'd imagine the people that did it probably couldn't tell you why the following morning. It's really a bit silly."

A spokesperson for the Broads Authority said: "The Broads Authority condemns anti-social behaviour such as this, and while it is a rare occurrence, it causes distress to those aboard boats and can damage surrounding moorings and infrastructure.

“The actions were in breach of a Broads Authority byelaw and any witnesses are asked to contact BroadsBeat with information by calling: 101 ext 1235 or 1236 or by email: broadsbeat@norfolk.pnn.police.uk.”