Four Dutchmen tried to smuggle a £16m haul of cocaine into Hunterston in a “James Bond” style underwater vehicle plot, a court heard this week.

Henri Van Doesburg, his son Roderick and grandson Darryl-Jay and Arnold Van Milt all appeared in the dock at Leeds Crown Court yesterday (Tuesday) charged with conspiring to import 108kg of the Class A drug through the North Ayrshire port.

A jury heard that Roderick, 23, Darryl, 22 and Van Milt, 49, who were trapped at Seamill Hydro after they were spotted by a customs officer who was staying there, obtained high-tech underwater diving equipment with the intention to access the drugs stashed in the hull of Columbian vessel the Cape Maria.

But the alleged plot was foiled when officers found the stash with a street value of £16.2million in the boat’s rudder house, which was accessible by divers from the outside, the court heard.

Opening the case against the four Dutch men, prosecutor Paul Mitchell told Leeds Crown Court: “After arriving from Columbia, investigators found 108kg of cocaine, that is £16 million worth of drugs concealed in the rudder housing of the Cape Maria.

“This was accessible from the outside of the boat by someone with access to scuba diving equipment. The defendants travelled to England with the intention of importing the drugs.” Mr Mitchell told the jury the four defendants travelled from Rotterdam, the Netherlands, first stopping in Cleethorpes, North East Lincolnshire. The defendants based themselves at a campsite in nearby Burton-upon-Staithes and took various trips on a rubber dinghy boat.

“On the first of May, a member of the coastguard noticed a small boat on the beach with men wearing drysuits walking away. The men were attracting significant attention in the town,” Mr Mitchell added.

Roderick and Darryl-Jay van Doesburg then left Cleethorpes on May 5 and drove with Van Milt to Scotland in a black Ford Explorer they had purchased under the name Ray Monty, Mr Mitchell added.

The jury heard Henri van Doesburg then flew back to Holland where he was later arrested after searches on a computer at his address found “significant” links between the four and the vessel importing the drugs.

Mr Mitchell said: “At 9pm that evening, the three defendants checked into Brisbane House Hotel in Largs, close to the mooring place place of the Cape Maria. They enquired about hiring diving equipment for three men.

The Cape Maria, having travelled from Columbia, was at Hunterston with the drugs stored in the back.

“Officers searched the rudder trunk space also accessible from the outside, where they found five large black packages containing 55 smaller packages with cocaine as high as 80 per cent purity.

“This was 108kg of cocaine in the vessel with a value of £4.3million. Cocaine is usually sold at 20 per cent purity, mixed with other powders so as to increase profits for drug dealers. The street value of this cocaine was £16.2million. These are extraordinary profits.

“This would have had a significant effect on the drugs market in the country as a whole.” The trio were arrested on May 9 at the four-star Hydro hotel in Seamill, where the Cape Maria was docked.

Mr Mitchell added: “The three defendants each had diving equipment, and Van Milt’s telephone had a document clearly relating to the Cape Maria, the boat with the drugs in.” Henri van Doesburg, 68, was arrested the next day in the Netherlands for his alleged part in the plot between February and May this year.

Mr Mitchell told the jury the three had planned to access the drugs by using high-powered underwater sea-bobs and scuba equipment.

He said: “In the car and in the inflatable boat, police later found dry suits and equipment you might have seen used by James Bond and his adversaries that you would use if you wanted to travel underwater at high speed.

“This is relevant when you consider the rudder house can be accessed from the outside of the boat.” Mr Mitchell added: “A customs officer happened to be staying at the hotel. He happened to notice the men and the inflatable boat outside the hotel. That same afternoon that police found the drugs. The defendants were still around in the area. Police by chance stopped the Ford Explorer.

“Officers noticed various camping equipment in the vehicle. The defendants were allowed to go on their way. All three were arrested that evening at the Seamill Hydro hotel.

“Is it all just a coincidence? The Crown say that it isn’t. These are the men who were behind the attempt to import the drugs.” Henri van Doesburg, Roderick van Doesburg, Darryl-Jay van Doesburg and Arnold Van Milt all deny conspiracy to evade the prohibition on the importation of controlled drugs. The trial continues.