Spanish police have warned of changing methods by drug gangs after finding 4.5 tonnes of cocaine on a livestock carrier off the Canary Islands.

The drugs were hidden inside a container of cattle feed on the 4,100-dwt Orion V (built 1973), police revealed on Sunday.

The vessel had stopped in various ports before the raid last Tuesday.

The ship had been under surveillance for over two years and had previously been “checked and searched, but no drugs could be found inside, despite the presence of sufficient clues”, police said.

The drugs have a street value of $114m.

The 28 crew members were arrested.

The vessel had arrived from Colombia. It was tracked by Spanish authorities, the US Drug Enforcement Administration and Togo police.

Officers were seen unloading dozens of boxes containing the cocaine at Las Palmas in Gran Canaria.

“International organisations are reinventing themselves to transport drugs from Latin America to Europe, using livestock [carriers] to make the control and localisation more difficult,” the Spanish police statement said.

Clean port state control record

The owner of the vessel is unknown, according to Clarksons, while IHS Maritime lists the owner as Sakai Global Inc of Florida since September when the vessel changed its name from FM Spiridon.

Sakai Global was not immediately available for comment.

The manager is listed as Safer Management in Lebanon, which could not be contacted.

The Orion V was last inspected as part of safety checks in Colombia in November and December, but no deficiencies were found. It was last detained by port state control officials in 2014.

Earlier in January, police found three tonnes of cocaine on a Greek-managed cargo vessel off the Canary Islands.

The 4,300-dwt Blume (built 2005) was intercepted 193 nautical miles (360 km) from the port of Santa Cruz de Tenerife, the Eldia Tenerife website reported.