SKOPJE, North Macedonia (AP) — Police in North Macedonia say they found six Afghan migrants hidden in a semi-trailer after a truck driver signaled that he suspected there were unknown individuals in his vehicle.

Police said in a statement Saturday that they discovered the six Afghans late Friday in the southern part of the country. They provided no details as to how migrants managed to enter the semi-trailer unnoticed, but said the driver signaled to a gas station employee to alert the police.

The migrants were transferred to a shelter center in the southern town of Gevgelija, near the border with Greece and will be deported.

Officially closed to migrant traffic since May 2015, the so-called Balkan route is still active as migrants cross over from Greece en route to wealthier Western European countries.