Spanish police have seized 40 pallets of compressed cocaine that was made to look like wood.
Around 1.4 tonnes of the drug was disguised as charcoal, according to officials.
The shipment arrived at the port of Valencia from Colombia.
Authorities suspect smugglers were using a Spanish charcoal company as a front as part of efforts to import the cocaine.
A laboratory in Madrid is suspected of having been used to extract the drug.
Twelve people have been arrested in Britain, Spain and Dubai as part of the operation, including two 'experts' said to have been responsible for the chemical extraction of the drugs.