BELGRADE (Reuters) - In a joint sting, Serbian and Croatian police have detained 17 people suspected of smuggling dozens of migrants into the European Union, Serbia’s Interior Ministry said on Wednesday.

Serbia was at the center of the migrant crisis in 2015 and 2016 when hundreds of thousands of people fleeing wars and poverty in the Middle East and Asia journeyed up through the Balkans to reach the European Union.

That route was effectively closed last year, but a steady trickle of migrants, arriving mainly from Turkey via neighboring Bulgaria, has continued. Many migrants use smugglers to reach the EU.

In a statement, the Interior Ministry said the group detained in Belgrade and four northern towns comprised 12 Serbians and one Afghan man. The police in neighboring Croatia have detained four more suspects, it said.

“It is suspected that this criminal group facilitated the illegal crossing of the border and transit ... to a total of 82 migrants from Afghanistan, Iran and Iraq, from whom they took 1,500 euros ($1,800) per person,” it said.

Official data show there are up to 4,500 migrants stranded in government-operated camps in Serbia. Rights activists say hundreds more are scattered in the capital Belgrade and towns along the Croatian border.

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