Belgian police have seized almost 4,000 kg of cocaine after being led to an address entered into navigation app Waze by two Dutch men, who were arrested on Tuesday, the local prosecutor’s office said in a statement on Wednesday.

Police had been informed of suspicious behavior late Tuesday evening in Ravels, a small town in the north of Belgium close to the Dutch border. Cars with Dutch license plates had been seen driving up and down a road.

They arrested two Dutch men, aged 27 and 46, who had a history of being involved in drug-related crime and who couldn’t give a satisfactory explanation as to why they were there. The men remain in custody.

Their navigation app led police to a nearby hangar with a container filled with 68 bags of cocaine, the weight of which the prosecutor’s office estimates at 4,000 kg.

Police also arrested seven other men who were present in the hangar.

The Belgium port of Antwerp, 55 km west of Ravels, has been coined Europe’s main entrance for cocaine. Last year, a record 110 tons of cocaine were intercepted there, accounting for 40 percent of all seizures in Europe, although local custom authorities estimate that is only 10 to 15 percent of the total cocaine smuggled into the port.

The European Union and Belgium announced earlier this month that they will step up their fight against organized drug crime.