Spanish Customs Surveillance intercepted the 69-metre merchant vessel San Trela about 60 nautical miles south-east of Cabo de Gata, Almería, on 13 May 2015 and found an estimated 5,000 kilos of hashish aboard.[1] A Tax Agency aircraft had spotted the vessel, flying the flag of the Democratic Republic of the Congo, sailing where vessels of its type are not typically found, with a rigid-hulled inflatable boat alongside transferring bales by crane.[1]

The patrol vessels Décimo Aniversario and Alca closed in with authorisation from the flag state, and officers arrested the six crew members, all Syrian nationals, seized the vessel and towed it to Almería, discovering a false bottom near the bow hiding the drugs on the way in.[1] The agency valued the haul at about 11 million euros, a provisional figure pending a thorough search at Almería port under judicial supervision.[1] It presented the seizure, under Operation Euphrates, as the thirteenth large hashish interception on the eastern Mediterranean route since May 2013, bringing that route’s running total past 115 tonnes, and later listed the San Trela among those seizures.[1][2] The detainees, the vessel and the drugs were to go before the duty investigating magistrate in Almería.[1]