435 people have been arrested as part of a Europol-coordinated operation which seized medicines worth €168m.
The crackdown by police, customs and health regulatory authorities took place across 16 countries, including Ireland.
The items seized were worth in the region of €168m, and included 13 million units and 1.8 tonnes of medicines.
24 organised crime groups were disrupted, and criminal assets worth €3.2m were recovered.
A garda spokesperson said they were looking into the extent of these arrests had occurred in Ireland.
The operation targeting the illegal trafficking of misused medicines took place over seven months from April to October last year.
The details of the actions were not released until today due to operational reasons.
An initial nine participating EU Member States (Ireland, Finland, France, Greece, Hungary, Italy, Romania, Spain and the UK) were joined by seven new countries this year (Belgium, Bulgaria, Cyprus, Lithuania, Portugal, Serbia and Ukraine).
The MISMED 2 was led by the French Gendarmerie Nationale (National Gendarmerie) and the Finnish Tulli (Customs), with support from Europol’s Intellectual Property Crime Coalition (IPC3).
Europol's investigations show that the type of medicines trafficked across Europe includes opioids but also products used for treating major illnesses such as cancer and heart conditions.
Performance and image enhancing drugs were also found.
The number of falsified or counterfeit products being trafficked is also increasing, with these accounting for over half of the 13 million units seized in the MISMED 2 operation.