Customs officials made their biggest cocaine haul of the year at Rotterdam port last week, when 4,180 kilos of the drug were found hidden in the roof of a container and among a consignment of bananas.

The find was made on December 30 and had a street value of €300m, officials said.

Once emptied, the container continued its journey to Antwerp port under police surveillance. From there it was moved to a warehouse in Essen, in Belgium. On Monday seven people were arrested at the warehouse – five Belgian and two British nationals.

In total, over 72 tonnes of cocaine was found at Dutch ports last year.