Frustrated migrants from countries such as Morocco, Algeria and Pakistan have tried to storm the Greek-Macedonian border, tearing down part of a barbed wire barrier and demanding to be allowed to continue their journey to northern Europe. A few ran across into Macedonia but were quickly detained by police.

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Migrants and refugees confront Macedonian police officers at the borderStoyan Nenov/Reuters
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A man shouts at Macedonian police officers at the borderStoyan Nenov/Reuters
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A man kneels and begs Macedonian police officers to allow him to cross the Greek-Macedonian borderYannis Behrakis/Reuters
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Migrants and refugees pull a barbed wire barrier as they try to cross the Greek-MacedonianYannis Behrakis/Reuters
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A man runs from Macedonian police officers as he tries to cross the Greek-Macedonian borderYannis Behrakis/Reuters
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A man runs through a field after crossing the border from Greece into Macedonia borderStoyan Nenov/Reuters
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A Macedonian police officer chases someone through a fieldYannis Behrakis/Reuters

They were among about 1,500 migrants who have been stranded by a policy of restricting entry only to those fleeing conflict. Slovenia, a member of Europe's Schengen zone of passport-free travel, declared it would only grant passage to those fleeing conflict in Syria, Iraq and Afghanistan, and that all others deemed "economic migrants" would be sent back. That prompted others on the route – Croatia, Serbia and Macedonia – to do the same, leaving growing numbers stranded in tents and around camp fires on Balkan borders with winter approaching.

Balkan countries have increased border security to stem what has been an anarchic, largely unchecked stream of humanity into Europe. The United Nations has condemned the restrictions, saying they are in violation of international law.

Those refused entry have sat through rain and rapidly decreasing temperatures while they hope that governments in the region will change their policy.

A group of Iranians have been staging a hunger strike and have sewn their lips shut in protest at the policy.

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A stranded Iranian man has his mouth sewn during a protest at the Greek-Macedonian borderYannis Behrakis/Reuters
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Stranded Iranians on hunger strike, some with their lips sewn together, sit on rail tracks at the border between Greece and MacedoniaYannis Behrakis/Reuters
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An Iranian man on hunger strike is seen at the border between Greece and MacedoniaYannis Behrakis/Reuters
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An Iranian man with his lips sewn together sits in front of others holding a banner denying they are economic migrantsMilos Bicanski/Getty Images
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Milob [right] from Afghanistan refuses to cross the Greek-Macedonian border if his Iranian fiancee Fariba is not allowed, tooSakis Mitrolidis/AFP
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An Iranian boy sits on rail tracks in front of riot police officersSakis Mitrolidis/AFP
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A Bangladeshi man looks through a police fence at the borderYannis Behrakis/Reuters
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African men take part in a protest at the border between Greece and MacedoniaYannis Behrakis/Reuters
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Pakistani men protest while waiting to cross the border from Greece into MacedoniaStoyan Nenov/Reuters
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An Iranian protests in front of police at the border between Greece and MacedoniaStoyan Nenov/Reuters
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An Iranian child sports the word "help" on her cheeksYannis Behrakis/Reuters
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Stranded people walk towards shelters during a rainstorm near the Greek-Macedonian borderYannis Behrakis/Reuters
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A stranded Pakistani migrant sits on a wall near the Greek-Macedonian borderYannis Behrakis/Reuters

A man named Barrawe from Somalia said that Europe was letting African refugees down in favour of those from the Middle East. "What we see is unfair because they let some people [through], they see only four years in war. We are into 25 years in war," he said.

Lubna from Pakistan begged the EU to help. "There is no food. The weather is cold. There is nothing. Nothing to eat, to drink. Please help us," he said.