Macedonian police fired tear gas to disperse around 50 refugees stranded in Greece, who tried to pull down part of the razor wire fence separating the two countries, a witness told Reuters. Scuffles briefly broke out and Greek riot police later intervened to break up the crowd, which had approached the border fence and chanted: Open the border!

Tensions have boiled over in recent days at the makeshift migrant camp near the town of Idomeni, where more than 10,000 migrants and refugees have been stranded since February, when Balkan countries shut their borders to anyone wanting to head north.

Hundreds of migrants were wounded on 10 April in clashes with Macedonian police, who fired tear gas and rubber bullets after a group tried to storm the border. The Balkan route was the preferred gateway into western and northern Europe last year for around one million migrants from the Middle East and beyond.

The migrants have refused to leave the site and go to official shelters, hoping to find a way to eventually cross the border and continue their journey to the rest of Europe. The Greek government said clearing out the makeshift camp that has mushroomed at Idomeni is one of its top priorities, but it does not want to use force.

Additional reporting by Reuters