"They will turn back all others on the basis they are economic migrants," the official said. Reuters was not immediately able to confirm the information with Slovenian authorities.
Syrians, Iraqis and Afghans make up the majority of the hundreds of thousands of migrants trekking across the Balkans in the hope of reaching western and northern Europe, mainly Germany and Sweden.
"As of 6 p.m. (1600 GMT) yesterday evening Serbia started turning back (to Macedonia) all but Syrians, Iraqis and Afghans," UNHCR spokeswoman Melita Sunjic said.
"Macedonia closed the border around 3 a.m and some 100 people remained stranded in no-man`s land."
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