It was the highest state of alert the government's medicines watchdog can issue.
By Paul Burnell
BBC File On 4
The MHRA issued four emergency drugs recall notices in June 2007
Eighteen months ago the Medicines Health products Regulatory Agency (MHRA) issued four of its Class One emergency recall notices in a matter of days to recoup thousands of packs of life saving drugs for stroke patients, men with prostate cancer and schizophrenics.
"Class One recall will be conducted where we've got some evidence to suggest we're dealing with a counterfeit medicine and it has got to patient level," Mick Deats head of enforcement at MHRA told BBC File On 4.
Three life saving medicines had to be recalled: Casodex, for prostate cancer, Plavix which is used for strokes and heart conditions and Zyprexa, which controls the symptoms of schizophrenia.
Said Mr Deats: "The meds involved had between 50-80% of the correct pharmaceutical ingredient in them."
A UK wholesaler spotted discrepancies in packaging of stock bought from in Europe.
According to former industry investigator Graham Satchwell reputable companies were duped by sophisticated counterfeits.
"All three medicines would have pretended to be medicines that were destined for other European markets, in the case of Plavix they would be a in a French language pack."
He said medicines from other parts of Europe can be bought at lower prices, and UK businessman can import from the EU under an arrangement know as parallel trade, and then repackage drugs into English language packs.
By the time the counterfeits were spotted, they were already in the NHS supply chain, distributed to chemists, doctors and hospitals and dispensed to patients whose lives were already at risk because of their illness.
Mr Deats said the MHRA had seized 40,000 of the estimated 70,000 packs of the fake drugs in the supply chain but issued the recalls because the other drugs were not accounted for.
"They would have been consumed by the patients," he said.
But File on 4 discovered there is no effective way of systematically tracing which patients may have received these drugs.
The Royal Pharmaceutical Society of Great Britain, confirmed that from wholesaler to chemist shops nobody is legally obliged to keep a record of drug batch numbers and the chemists do not keep records of which patient is dispensed drugs from which batch.
When the emergency was announced it was left to individual chemists to warn their regular patients.
Neither is it known if the 70,000 packs were part of a larger consignment or consignments.
"You can never tell if you have got it all. And don't forget we're not dealing with lawful manufacturers who know how much their batch contains," explained Mr Deats.
What is known is that the same batch numbers from the drugs were traced to the man at the centre of an international fake drugs ring, Kevin Xu, a citizen of the People's Republic of China and owner of Orient Pacific International.
Xu smuggled goods and trans-shipped them from China into another country, shielding them from customs investigations by packing them into drums of chemicals, and then shipping to various ports throughout Europe.
Marcy Foreman director of the Office of Investigations for US Immigration and Customs Enforcement, (ICE), told File On 4, "Mr Xu was a very sophisticated international businessman and he had a vast knowledge of the import and export requirements.
"And the bottom line is that his motivation was simply about the money and ultimate greed."
The MHRA said it has learned lessons about weaknesses in regulation, practice and EU directives following this and other cases it has investigated, although Mr Deats conceded this will be little consolation to any of the patients with serious illnesses who took any of the fake drugs.
American officials believe Kevin Xu had ambitions to to break into the US market, when he was arrested in a sting by ICE officers. He began a six and a half year jail sentence three weeks ago.
The fate of his potential British victims may never be known because no-one knows who took the drugs, and because of that, no-one knows whether anyone died as a result or what effect it has had on people's treatment.