Twenty Filipino seafarers were arrested in Nigeria after authorities intercepted around 20 kilos of cocaine hidden aboard a Panama-flagged vessel docking at the port of Lagos, the country’s drug enforcement agency reported Friday.

The National Drug Law Enforcement Agency (NDLEA) said the intercepted drug, described as “top-grade,” was recovered on Sunday. It was buried beneath the ship’s cargo, which usually transports coal between Brazil and Colombia.

The all-Filipino crew members were taken into custody pending the investigation, the NDLEA added.

Earlier this month, the agency said it was working with the United States and United Kingdom to pursue a cartel tied to the importation of 1,000 kilograms of cocaine found in a container at the Lagos port.