Police and customs officers from 81 countries have seized 2.4 million doses of counterfeit medicine sold over the Internet during a one-week operation, international police body Interpol said Thursday. Fifty-five people were arrested during the September 20-27 operation, codenamed Pangea 4, and more than 13,000 websites closed down, Interpol said. More than 100,000 illegal doses were seized in France, over half of which were for supposed to be for treating erection problems, the French medical security agency that took part in the operation, AFSSAPS, said. The operation was carried out for the fourth successive year in an effort to inform the public about the risks of buying medicines online.