More than a million fake versions of Pfizer's anti-anxiety tablet Xanax have been seized and destroyed at Zurich airport.

News of the haul came from Swissmedic which had been informed by Switzerland's customs about four crates containing the counterfeit Xanax (alprazolam) which weighed over 400 kilogrammes. The regulatory agency then intercepted the shipment, which was in transit between China and Egypt, and requested samples.

Analyses revealed that the drugs "contained no active ingredients whatsoever" and Swissmedic says that according to experts, the products "would be unrecognisable as counterfeits at a first glance". The agency says it immediately informed international authorities, in particular the Egyptian and Chinese, and ordered the destruction of the drugs.