A South Oxhey man who led a bungled plot to smuggle cocaine with a value of £10 million into the country was jailed for 21 years today.

Patrick Walsh, 48, of Blairhead Drive, was seized by armed police in September 2008 as he prepared to commit an armed robbery at a petrol station in Denham.

He was one of five men sentenced today at Woolwich Crown Court for their role in a plot to smuggle the drugs from the Caribbean by sea.

The Metropolitan Police Service said Walsh had masterminded an organised criminal conspiracy.

Flying Squad officers began investigating back in November 2007, when they observed Walsh and an accomplice scouting locations for future armed raids.

The investigation gathered pace in January 2008, however, when the force became aware of the drug smuggling conspiracy.

Surveillance officers kept watch as Walsh made repeated trips to Trinidad, Tobago, Barbados and Grenada, using the false name of Michael Sheridan. There he purchased a boat for $40,000.

He was later observed finalising the scheme with meetings at motorway service stations and even a burger stall in Lakeside, Thurrock.

On July 20, 2008, co-defendants David Coxon and Douglas Wood set sail from Grenada, falsely telling customs they were heading to Brazil. Instead they headed for Bartica, Guyana, where they are believed to have picked up 91.3 kilos of high quality cocaine straight from the South American jungle.

Walsh was arrested September 5, 2008, at the Total petrol station in Denham, where he was found sitting in a car with a handgun, live ammunition, two balaclavas, gloves and laundry bags. The delivery van he was waiting for, however, had been diverted by armed police officers.

In the meantime Coxon and Wood were crossing the Atlantic Ocean on route to Portsmouth. Their boat, named Ronin, was stopped by the Royal Navy in the early hours of September 12. The cocaine, with a street value of £10 million, was found on board.

Walsh pleaded guilty on September 23 to conspiracy to import the cocaine and possession of a handgun with intent to commit robbery. He later admitted his plan to rob a security van loaded with cash.

Detective Superintendent Bob Cummings, from the Serious and Organised Crime Command, said: "This investigation shows how the Met will use all the opportunities open to us to ensure that no matter how many pies criminals try to have their fingers in then we will be there to ensure that guns are taken off the streets, drugs are stopped from reaching our shores and cash in transit deliveries can go about their lawful business without criminal threats.

"This was a complex international and UK operation that involved close working with a range of partner organisations.”