In early September, Spanish authorities seized an 800-kilogram shipment of cocaine aboard a yacht whose four crew members included two Estonians, police said on Thursday.
Investigators said they intercepted a ring that was smuggling drugs from Latin America to Europe, reported Interfax.
In connection with the yacht, police arrested a total of 16 people and seized another vessel, vehicles, a firearm and cash.
Of the other two crew members, one was a Serbian and the other a Spanish national.
The vessel was seized in international waters near Portugal's Azores islands.