The drugs were found during checks carried out on vehicles by the Highways Police on Thursday. An identity check on the driver of the French-registered vehicle found that he was being sought for other drugs-related offences.
Police also found drugs in another vehicle they searched. The Dutch driver of the car and his passenger were found to be in possession of 500 ecstasy pills, 200 grammes of cannabis, 110 grammes of cocaine and 1kg of the amphetamine mephedrone. The two Dutchmen in the car are 20 and 21 years old.
The drivers of both vehicles will appear before an Examining Magistrate in Ghent (East Flanders). The passenger of the second vehicle was released after questioning.
Elsewhere in East Flanders a 53-year-old Dutch national was detained after 12.6 kilogrammes of cannabis was found in his car at Kruisem. He will appear before an Examining Magistrate in Oudenaarde.