Six men including a Briton have been arrested off the coast of Plymouth after authorities seized more than two tonnes of cocaine worth around £160 million.

The National Crime Agency (NCA) said an operation involving its personnel as well as the Australian Federal Police (AFP) and Border Force arrested the British man from Stockton-on-Tees, County Durham, and five Nicaraguans aboard a Jamaican-flagged yacht 80 miles out to sea.

Border Force Maritime Command’s 42-metre cutter Searcher and 19-metre coastal patrol vessel Alert had covertly identified and monitored luxury yacht Kahu’s movements.

Kahu, which was sailing from the Caribbean, was intercepted and boarded by specialist highly-skilled Border Force and NCA officers in international waters north of Guernsey.

The yacht was then escorted back to an undisclosed location on the UK mainland where a team carried out a deep rummage search and discovered the enormous haul of Class A drugs.

The men, whose ages range from 24 to 49, were arrested on suspicion of drug trafficking and remain in custody awaiting interviews, the NCA added in its statement.

NCA deputy director Matt Horne said: “There’s no doubt these drugs would have been sold on into communities across the UK in such ways as County Lines fuelling more crime and misery.

“Organised crime groups (OCG) are motivated by money.

“The deprivation of these drugs will smash a hole in the OCG’s plans and ability to operate.

“Also, the arrests of the men transporting the drugs means the crime group has lost trusted offenders who would have been key to their operation.

“We continue to work with partners at home such as Border Force and those abroad such as the AFP to protect the public from the Class A drugs threat.”

The NCA said the arrests demonstrate the strength of its international partnerships, working with the AFP who as part of the operation used evidence from their Operation Ironside, the country’s investigation into the AnOm encrypted comms platform.

AFP assistant commissioner Lesa Gale, said: “Intelligence from Operation Ironside had enabled the AFP to assist international enforcement partners in disrupting an alleged sophisticated criminal network.

“Operation Ironside has opened the door to unprecedented collaboration across law enforcement agencies around the globe.

“This result highlights the importance of the AFP’s partnership with the NCA to combat offshore transnational organised crime that impacts both of our countries.

“The AFP and NCA have a strong, historic relationship and both agencies recognise the significant threat to national security posed by transnational organised crime.”