A British yacht captain has told how a pod of killer whales sunk his £100,000 boat during a "terrifying" two-hour attack - in the Mediterranean Sea.

Robert Powell, 59, said the pack of five orcas encircled his 39ft sailing boat ‘like wolves’ and took it in turn to smash into the ship as he sailed off the coast of Spain.

He and two crew were 22 hours into a ten-day trip between Vilamoura, in Portugal, and Greece when the animals began their violent “attack” at 8pm on Wednesday, roughly two miles offshore.

After they knocked out the boat’s rudder, the animals spent the next few hours “taking it in turns” to charge into it - causing the vessel to buckle under the pressure.

Robert, who had radioed for help not long after the orcas began their assault, said he and his crew had felt like “sitting ducks” as they waited for rescue.

And just minutes before the boat sunk, a Spanish salvage vessel helped them leave their stricken ship, which is now 130ft below the Mediterranean Sea.

Robert said about the ordeal: “Once the rudder was disabled, all five orcas circled the boat. And one by one they kept coming in and ramming in various different places.

“They’d ram the keel, ram the stern. The boat, with no rudder, just goes around in circles. They were circling. It was like watching wolves hunt.

"They were taking it in turns to come in – sometimes two would come in at the same time and hit it. So obviously pretty terrifying.

“It was a very long attack, and it was really the violence of the attack that surprised me.

“To me they were not playing at all, they knew exactly what they were doing. They knew the weak points of the boat and they knew how to sink it.

"Their sole intention was to sink the boat, and that was it.”

Orca attacks on sailing ships in the Mediterranean have increased recently - with another boat being sunk in May in the Straights of Gibraltar after getting rammed.

Robert, who lives in London, believes the pod that attacked and sunk his vessel could be the same that has been terrorizing other skippers

He added: “I’ve heard of a group that operates around that area. I’ve sailed it before, I sailed it last year.

"I know other people who have been hit. They’ve not had their boats sunk but have had it damaged badly.

"And I have a feeling that this group are boat sinkers – I think they knew what they were doing, I’m sure of it.”

Robert set out in his boat, the Bonhomme William, from Vilamoura, on Portugal’s Algarve coast, for the ten-day trip to the Greek Islands to celebrate his 60th Birthday on Tuesday (23/7).

But as the IT company owner sailed with two crew, a deckhead and a chef, he was hit by the first orca between the Spanish towns of Barbate and Tarifa at around 8pm.

Robert said: “All of a sudden I felt something really hard hit the bottom of the boat.

“My initial reaction was that I’d hit a rock or fishing net – or I’d hit something submerged – and it shuddered the whole boat. It was a big hit.