More than 100 kilos of suspected Class A drugs have been seized following investigations by Thames Valley Police and Dutch law enforcement.
Last month, a shipment from overseas destined for a village in Hertfordshire was intercepted and searched.
Officials from the Border Force recovered 45 kilos of suspected heroin, which was concealed within the consignment.
The investigation led to the arrest of two men from Milton Keynes in connection to the shipment.
The men, one in his 40s and the other in his 20s, have since been charged with drug offences in connection to the seizure.
A man in his 40s from Hertford was also arrested, and has since been released on bail.
An investigation found an additional two shipments were due to be sent from Holland to the same Hertfordshire location.
Officers were able to work with Dutch law enforcement to locate these shipments, which were found to contain around 70 kilos of suspected cocaine.
Detective Sergeant David Skarratts said: “These are major seizures of suspected Class A drugs, only possible because of some fantastic detective work and investigations which saw us working alongside international colleagues.
“Large scale importation of cocaine and heroin has a corrosive impact on our communities, as it can fuel the rise of things like county lines and risk of associated serious violence and exploitation of children and other vulnerable people, so it is great these seizures have been prevented from entering the illicit drug supply chain.”