Police in China and South Africa have seized thousands of doses of fake Covid-19 vaccines and made more than 80 arrests after uncovering a criminal network that was distributing counterfeit jabs, according to Interpol.

The export scam was found out after police in eastern China identified a network selling counterfeit inoculations. Officers raided a manufacturing premises and found more than 3,000 fake vaccines. More than 80 people were arrested.

Separately, South African police officers found 400 ampoules of fake vaccine, enough for about 2,400 doses, at a warehouse just outside Johannesburg. The officers also confiscated a large quantity of counterfeit masks and arrested three Chinese nationals and one Zambian.

The joint investigation was co-ordinated by Interpol’s illicit goods and global health programme, which has been working to prevent criminals from exploiting the disruption caused by the pandemic.

Jürgen Stock, Interpol’s secretary-general, warned that the discovery of this network represented “only the tip of the iceberg” of vaccine-related crime. The agency is tracking other reports of fake vaccine distribution and scam attempts targeting health bodies, such as nursing homes.

Interpol highlighted in December the growing risk that criminal gangs would seek to capitalise on the global demand for Covid-19 vaccines by either selling fake inoculations or stealing real ones. The agency said the pandemic had already triggered “unprecedented opportunistic and predatory criminal behaviour” and urged its 194 member countries to foster close co-operation between police and healthcare officials.

Research by the Financial Times has already exposed the boom in vaccines for sale on the dark web, with vendors offering “stealth delivery”, overnight shipping, and demanding payments in bitcoin. Experts said many of the shots advertised were either fake or would never be sent.

Security officials in the UK and the US have issued separate warnings that vaccine research is increasingly becoming an espionage target for hostile countries that might also seek to disrupt supply chains.

Last summer, Britain’s National Cyber Security Centre, a branch of GCHQ, said Russian state-backed hackers had targeted pharmaceutical companies and academic institutions involved in vaccine research in the UK, US and Canada. The US has accused China of hacking US healthcare and research institutions working on Covid-19 vaccines, treatments and testing.

Brigadier Vish Naidoo, national spokesperson for the South African police, welcomed Interpol’s co-ordination efforts in helping to apprehend “foreign nationals attempting to peddle fake vaccines to unsuspecting people” in his country. South Africa has so far administered only 70,500 doses, equivalent to 0.1 doses per 100 residents, according to the FT’s vaccine tracker.

A spokesperson for China’s ministry of public security said the Chinese government attached “great importance” to vaccine security.

“Chinese police are conducting a targeted campaign to prevent and crack down on crimes related to vaccines, proactively investigating and combating crimes related to vaccines in accordance with law,” the spokesperson said.