The gang, based in the northeastern town of Olivella, received the drugs from Asian countries labeled as legal products, they said in a statement.

They were then mixed and prepared at their laboratory and sold online with names like “Diablo,” “Dream potpourri”, “Atomic fever” or “XXX Plant food,” to countries that included Australia, Britain, Russia, Germany, the United States and Japan.

“One of the substances seized was methedrone, the effects of which are similar to cocaine or amphetamines and which has caused several deaths in the United Kingdom,” it said.

“Those arrested marketed it as a fertiliser for plants.”

Other substances found at the lab include methylone, phenethylamine benzophenone and lidocaine.

Altogether police seized 98 kilogrammes (215 pounds) of stimulants, more than 9,000 tablets, almost 1,700 capsules more than 2,000 hermetically sealed envelopes with powered substances inside.

The four Lithuanians arrested have been charged with drug trafficking offences.

Spain’s proximity to north Africa, a key source of hashish, and its close ties with its former colonies in Latin America, a major cocaine producing region, have made it a major gateway into Europe for drug traffickers.