They claimed traffickers are playing with the lives of revellers by testing synthetic drugs on them – before peddling them around the rest of Europe.
Raul Izquierdo, a health officer for the Balearic islands, has warned that such drugs are ‘especially dangerous’ because of their ‘unknown side effects.’
He added: Ibiza is the gateway, and the experimental laboratory for the new drugs that appear.
Lethal stimulants Methylone and PMMA are among the most common seizures of new designer drugs on Ibiza in recent years, although marijuana and cannabin resin still top the confiscation tables.
Local authority figures shows that the number of drugs seizures in the Balearics Islands rose from 14,253 in 2012 to 18,640 last year.