DART harbour staff are on alert after a boat being used as part of a people smuggling operation was stopped at nearby Salcombe.

The harbour office says staff are remaining vigilant at all times and are fully briefed on reporting any suspicious activity in the port.

The reassurance comes following an incident in Salcombe in early May when suspicions were raised about a yacht which entered the harbour.

It was later found to be part of a smuggling ring smashed by French police in which migrants paid up to £5,400 per person for a door-to-door service from their home country to the English coast.

The yacht’s crew were seen to be acting in an unusual way with regard to their attitude, behaviour and seamanship.

This alerted the moorings team who thought it was acting suspiciously.

They then contacted the police and Project Kraken – a crime and counter terrorist project in harbours and estuaries.

The next day the boat was inspected by members of the Special Branch Counter Terrorism Unit and police divers. Although nothing was found on that occasion, it potentially contributed to a wider ongoing operation, with positive results.

The boat was later found to be part of a smuggling ring, using pleasure yachts to transport illegal migrants to Britain, and the crew are currently under police arrest.

Dart Harbour said staff were fully briefed on Project Kraken, the communication channel for reporting suspicious activity in ports and around the coastline.

Deputy harbour master Nick Clarence said: ‘Staff are trained to be vigilant and to report anything of a suspicious nature taking place in the Dart, and Dart Harbour has a good working relationship with other agencies including the police.

‘This is obviously ongoing, with staff remaining vigilant at all times.’

Salcombe harbour master Adam Parnell said: ‘I’m delighted that my team acted upon their suspicions that “something wasn’t quite right” about this boat, and followed the advice of Project Kraken.

‘By informing the police and Project Kraken, they set in train a series of inspections on the boat by counter terrorism and police dive teams.

‘This ultimately contributed to their arrest by the French authorities.’

Project Kraken delivers a crime and counter terrorist vigilance expertise within the maritime environment of the harbours and estuaries around the South Hams. It is part of a National Maritime Security Strategy with 90 per cent of UK police forces having the responsibility for a coastline and inland waterways.

South Hams district councillor Rufus Gilbert said: ‘The team in Salcombe have obviously got their eyes open to potential traffickers and will spot anything unusual coming in or out of the harbour.

‘A fantastic job of partnership working with other agencies to share marine intelligence, which resulted in the eventual arrest of these people.’

A report in the Daily Telegraph said French police had smashed the smuggling network that used pleasure yachts to take illegal migrants to Britain more than 20 times, after finding seven Ukrainians stowed on one vessel in Brittany.

Four suspected people smugglers of Ukrainian nationality, two of them the yacht’s skippers, have been placed under formal investigation over the affair in which migrants paid up to €7,000 (£5,400) per person for a door-to-door service from their home country to the English coast.

Police said the smugglers had rented boats from various ports along the French coast over the past two years, suggesting that up to 200 migrants had made it to the UK, mostly undetected by British authorities.

‘This ring, active since 2012, organised at least 20 crossings of illegal migrants,’ said Nicolas Jacquet, the public prosecutor of Rennes.

The Telegraph claimed better-off migrants were paying up to £10,000 a head to be smuggled into the UK by speedboat, yacht and light aircraft.

Calais police said they believed that Albanian gangs controlling Europe’s multi-million pound trafficking industry are ‘diversifying’ routes into Britain after security was increased at ferry ports and the Eurotunnel network.