Serbian police have rounded up more than 200 migrants in the country's north following reports of alleged attacks against the local population.

The raid early Tuesday morning happened in the town of Sid on the border with Croatia.

The migrants, who allegedly did not register with local authorities, were packed into buses and sent to southern Serbia and the border with Macedonia.

They are mostly from Afghanistan and Pakistan.

Only the elderly, women and children were allowed to remain in a local refugee center.

Sid Mayor Predrag Vukovic says the migrants "stole, fought among each other and attacked the locals".

Thousands of migrants seeking to reach European Union countries have been stranded in Serbia since neighbouring Hungary and Croatia battened down their borders.