One of the largest amphetamine factories ever found in the UK that was built by a Chalfont St Giles man is shown in a shocking new video. 

The drugs lab could produce 881lbs (400 kilos) of amphetamine each month, worth £2 million at wholesale and up to £10 million at street level.

Ringleader John Keet, 41, from Chalfont St Giles, invested profits from a career dealing cocaine, cannabis and amphetamines into building and managing the lab near Redditch. 

He paid for his right hand man, Keith Davis, 62, also from Chalfont St Giles, to take chemistry training to enable him to operate the site.

Work started on the building in March 2020 and it began producing drugs in May that year, police said.

The gang initially bought amphetamine precursor chemical benzyl methyl ketone (BMK) but quickly realised it was more profitable to make it themselves.

The haul of drugs were distributed from the factory near Redditch in Warwickshire to dealers in the West Midlands, London and Kent.

Plumes of noxious fumes billowed from the outbuilding when it was opened by fire crews, who had to wait several hours before searching it due to the hazardous chemicals inside.

One member of the crew - Andrew Gurney, 51 - was known as ‘The Geek’ because of his specialist electrical installation and plumbing skills, had converted a double garage outbuilding into the drugs lab.

National Crime Agency (NCA) officers and Warwickshire Police raided the site in Ullenhall Lane, Henley-in-Arden, Warwickshire, last April 27.

Waste products from the production process, which had been flushed into the sewerage system, had also contaminated a nearby field.

Electronic weighing scales were found in Davis’ home, along with 300 kilos of BMK at a storage facility he used.

A string of documents and receipts were also found by cops in Gurney’s vehicles relating to heating equipment identified in the lab, weighing scales and chemicals needed for amphetamine production.

Officers also found PPE, including respirators and wellington boots which had chemical traces of amphetamine on them.

As reported in the Bucks Free Press last week, Davis, and Gurney, of Quinton in Birmingham, were found guilty following a 12-day trial at Kingston Crown Court. 

Davis was jailed for five years and three months, while Gurney was sentenced to six years and three months in prison at the same court on Friday. 

Keetpleaded guilty to all the charges at the same court on October 29 last year. He is due to be sentenced in August.

Elliott Walker, 49, of Kidbrooke, south east London, was an associate of Keet and bought specialist equipment for the lab.

He pleaded guilty to conspiracy to produce class B drugs - amphetamine - last September 17 and was jailed for six years on December 14.