A sharp rise in the supply of counterfeit drugs, fuelled by the use of the internet, has been highlighted by a series of prosecutions by British regulators.

In the most high-profile case , Ashish Halai was last month sentenced at Kingston Crown Court to four-and-a-half years in prison, following a five-year investigation dubbed Operation Stormgrand. Investigators called him the linchpin in an operation that bought fake medicines worth millions of pounds from Asia to the UK for sale and re-export.