Thousands of superferry passengers were delayed after a legal challenge by the family of a fisherman swept overboard by its bow wake "arrested" the vessel.

A Marine Accident Investigation Bureau report recently confirmed Marilyn Sibley's claim that her husband fell overboard after the fishing boat Purdey was rocked by the HSS Discovery as it approached Harwich.

Non-swimmer John Sibley, 47, of Spruce Avenue, Greenstead, Colchester, was not wearing a life jacket when he was swept from the 33ft boat off the coast of Felixstowe. He was eventually found 11 days later.

On Friday , solicitors acting for Mrs Sibley put an arrest on the Discovery, preventing it from sailing.

Stena Line said it was "shocked" by the decision to arrest the ship, which it branded "totally unnecessary".

A statement said: "The company has never received a claim from the family of Mr Sibley and has never been asked to provide security.

"Stena Line was also surprised, given the assets of the company and its ability to meet any judgement, that this course of action was taken.

"It was not necessary to arrest the ship to obtain security. Stena Line's solicitors advised the legal representatives of the Sibley family that security would have been provided without the need to arrest the ship. It has only served to inconvenience thousands of holidaymakers."

The Discovery was delayed from leaving Harwich for more than an hour while the legal situation was sorted out.

Mrs Sibley's solicitor, Andrew Higgs of London-based Davies Arnold Cooper, said this was a standard procedure made with a view to following a claim for compensation, but he said the Discovery was later released after a £500,000 security for the claim was put up by the Swedish Protection Indemnity Club.

"The claim will now follow a normal course but we are hoping that it will be in court within a year. The basis of our claim is we are asking them to accept liability," said Mr Higgs.

The case would be heard in the Admiralty Court, a division of the High Court, in London.

Mr Sibley had two daughters, Penny and Joanna, and three grandchildren.

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