More than 1,000 migrants and refugees arrived in EU member Hungary late Monday, the first of around 7,000 who found their gruelling journey to Europe blocked when Macedonia declared a state of emergency last week.
An AFP photographer said at least 1,000 people entered Hungary from Serbia via a cross-border railway track, close to the southern Hungarian village of Roszke.
Their arrival comes just days before the Hungarian government deadline of August 31 for the completion of a razor-wire barrier along the length of its southern border with Serbia -- which is not a member of the EU -- in a bid to keep migrants out.
The group -- most of them refugees from war-torn Syria -- arrived at a section of the border not yet fenced off by razor-wire. They were met by Hungarian police who escorted them to a nearby refugee registration centre, according to Hungarian state news agency MTI.
Many told AFP they had passed through Serbia after travelling from Macedonia`s border with Greece -- which Macedonia closed for three days last week, declaring a state of emergency after being overwhelmed by the huge influx of people amid Europe`s worst migration crisis since World War II.
There were chaotic scenes on Friday as Macedonian police lobbed stun grenades at desperate migrants trying to cross newly-laid rolls of barbed wire at the frontier.
At least 7,000 people made it north to Serbia after Macedonia finally reopened its Greek border on Saturday.
The group are hoping to follow roughly 100,000 others who have crossed over into Hungary -- their entry point to the European Union after the Balkans -- which has responded with aggressive anti-migrant measures, including the razor-wire barrier.
Hungary is also building a 4-metre (13-foot) fence behind the razor wire, while Budapest plans to pass legislation in September to criminalise illegal border-crossing or any attempts to cut through or climb over the fence.
The interior ministry also gave the green light Monday to the deployment of special police units of "border hunters" to intercept migrants.
The "western Balkans route" has now become one of the main ways into the EU for the several hundreds of thousands of migrants entering the bloc this year, fleeing war, poverty and persecution in the Middle East, Africa and South Asia.