Serbian authorities have arrested 17 people suspected of trafficking hundreds of illegal immigrants from Africa and Asia to western Europe.

Police officials say the arrests were made Tuesday in raids across the country.

Separately, Serbian police stopped at least 12 illegal migrants as they tried to cross into Serbia from Macedonia. Customs officials say the migrants from Somalia and Afghanistan were hidden in a truck registered in Macedonia.

Serbia and Macedonia are part of the so-called Balkan route used by organized crime gangs to smuggle drugs and people into western Europe.