A British couple could face 20 years in a US jail after being arrested on claims that they supplied a huge amount of chemicals to US crystal meth labs.
They are alleged to have supplied chemicals to US crystal meth labs
Officers allege that Brian Howes, 43, from Middlesbrough, and Kerry Ann Shanks, 28, from Bo'ness, created a "one-stop shop" for drugs producers.
They said the pair sold enough chemicals to make 1,400lb of the drug with a street value of £6.4m ($12.6m).
Extradition proceedings have begun at Edinburgh Sheriff Court.
Their arrest follows a two-year investigation nicknamed Operation Red Dragon into production of the deadly Class A drug involving three UK forces - Central Scotland Police, Cleveland Police and Scotland Yard.
These officers were working in conjunction with the US Drug Enforcement Agency (DEA) and the Serious Organised Crime Agency (Soca) as well as other law enforcement agencies in the US.
Officers from Central Scotland Police made the arrests in Bo'ness, near Falkirk, on Tuesday.
The move followed an indictment handed down by a grand jury in Arizona which alleges that the couple sold chemicals through their website - including red phosphorus and iodine - which are used to manufacture methamphetamine.
US District Attorney for Arizona, Paul Charlton, said Mr Howes and Ms Shanks were suspected of supplying a global network of meth labs in the US, Europe, Australia and New Zealand and other countries dating back to 2004.
A conviction for unlawful importation and distribution of regulated chemicals such as red phosphorus carries a maximum penalty of 20 years, a $250,000 (£128,268) fine or both.
Mr Charlton added that the couple's website came to the attention of the US authorities after investigators in Arizona uncovered numerous clandestine methamphetamine - crystal meth - labs in the US state which purchased their chemicals through the site.
He added that between August 2004 and November 2006, the website sold approximately 319,000 grams of red phosphorus and 45,950 grams of red iodine to US customers - enough to make over 1400lb of methamphetamine.
This, Mr Charlton said, would have a wholesale value of $12.6m (£6.4m).
He said: "Internet criminals rely on the world wide web to provide them with a borderless weapon and anonymous shield.
Brian Howes is accused of running a lucrative drugs service
"We have demonstrated how law enforcement authorities around the world can work across borders to identify and dismantle operations like this."
It had been alleged that the couple started the business in England, but moved it to Scotland after a raid.
Mr Charlton said their website, which advertised "discreet" delivery to customers around the world, received numerous e-mails from customers indicating they were unlawfully using the chemicals purchased from the website.
As well as the arrests on Tuesday, police also swooped on business addresses in Bo'ness.
A major police operation in June, involving up to 250 officers, saw a raid on the couple's alleged distribution centre in Grangemouth.
Police said Mr Howes and Ms Shanks had lived for some time in Cleveland.
The couple were remanded in custody when they appeared in court on Wednesday, with further proceedings expected in March.