Hundreds of migrants are stranded at the Serbia-Hungary border after the Hungarian government closed the frontier with a new razor-wire fence.
The move aims to stop migrants who are trying to enter the EU.
After new Hungarian laws came into effect overnight, police sealed a railway crossing point that had been used by tens of thousands of migrants.
Some have been searching for a way through the fence, while others threw down food and water in protest.
Hungarian Foreign Minister Peter Szijjarto has suggested his country is planning to build a fence to keep migrants out along part of its border with Romania – a fellow EU member – to prevent the bypassing of the current frontier.
The EU is facing a huge influx of migrants, many fleeing conflict and poverty in countries including Syria, where a civil war has been raging since 2011.
