"The probe showed that this big organization, made up mainly of Tanzanian traffickers, was providing Europe, Britain, Switzerland and Turkey with cocaine from Argentina and Brazil," the top prosecutor's office in the canton of Geneva said in a statement.

Geneva airport police had since October 2010 worked with police in other Swiss cantons, as well as in Belgium, Canada, Portugal, the Netherlands, Argentina and Brazil to track down the traffickers, the statement said.

Nine kilos (20 pounds) of cocaine had been seized in Geneva, 24 in Argentina, seven in Brazil, 2.5 kilos in Belgium and 2.5 kilos in Portugal.

"Basically all of the drugs seized abroad were destined for Switzerland," the Geneva prosecution said.

In all, 15 drug traffickers were arrested around the world, including seven people in Geneva.

During the investigation, police pinpointed one of the heads of the ring, in Argentina. He was arrested a year ago, and they also caught up with the trafficking coordinator working out of Britain last April.

Police also uncovered important buyers in the Netherlands and Switzerland, and had intercepted a mule-recruiter based in Switzerland along with several mules, or transporters.

Geneva police however pointed out that a lot of drugs had made it to their destination.

"This long investigation has made it possible to determine that the ring has imported at least 90 kilos of cocaine to Switzerland, in addition to the seized (drugs)," the police said in a separate statement, adding that the quantity was likely much higher.

A Brazilian police probe had showed that the ring had at times bought between 12 and 15 plane tickets a day from a Sao Paulo travel agent for its mules heading to Europe.