SARAJEVO, Bosnia-Herzegovina (AP) — Bosnian border police have stopped about 100 migrants from reaching the border with European Union member Croatia amid a rise in the influx of people heading through the Balkans toward Western Europe

Police blocked the migrants near the border crossing in northwestern Bosnia, which was closed down. Migrants then set down on the road as police tried to persuade them to turn back.

The group has moved toward Croatia from the nearby town of Velika Kladusa, where hundreds have been staying in makeshift camps while looking for ways to move on.

Migrants have recently turned to Bosnia in order to avoid more heavily guarded routes through the Balkans. Authorities in the war-ravaged country have struggled with the influx of thousands of people from the Middle East, Africa and Asia.

Peter Van der Auweraert, from the International Organization for Migration, tweeted that the attempted group crossing on Monday was a "very worrying development that risks" creating a backlash.

Van der Auweraert explained in a phone interview with The Associated Press that the migrant influx has already put pressure on postwar Bosnia and any incidents could further strain the situation. Bosnians might start viewing migrants as "troublemakers" rather than people in need of help, he said.

Migrants arrive in Bosnia from Serbia or Montenegro after traveling from Greece to Albania, Bulgaria or Macedonia.

The International Federation of Red Cross and Red Crescent Societies said Monday that more than 5,600 migrants have reached Bosnia and Herzegovina so far this year, compared with only 754 in all of 2017.

The Red Cross also said that in Montenegro, to the southeast, 557 asylum requests were registered in May, the highest monthly figure in five years.

Hundreds of thousands of people passed through the Balkans toward Europe at the peak of the mass migration in 2015. The flow eased for a while but has recently picked up pace with the new route through Bosnia.