More than 2,000 fake weight loss jabs, worth more than a quarter of a million pounds, have been seized from a warehouse in Northampton.
The Medicines and Healthcare products Regulatory Agency (MHRA) said it is the first illicit production facility for weight loss medicine discovered in the UK.
During the search, MHRA officers and Northamptonshire Police seized tens of thousands of empty weight loss pens ready to be filled, raw chemical ingredients.
The once-a-week jabs, made by pharma giants Novo Nordisk and Eli Lilly are meant to treat type 2 diabetes, but also help reduce weight.
They are available in the NHS to a limited number of people, depending on their obesity levels and health conditions.
It is estimated that in the UK, thousands of people buy them privately, and it is in great demand.
Following pressure from US president Donald Trump to lower medication prices for Americans, Mounjaro maker Eli Lilly had sharply increased its price in the UK.
This has given rise to the proliferation of spurious drugs in the market.
Experts have repeatedly warned people from buying the jabs on social media and to be aware of scam online retailers posing as pharmacies, over fears they may be selling contaminated versions of the blockbuster injections.
Doctors have also told how patients have suffered seizures and have even been left in life-threatening comas.
