
Violence erupted at an over-crowded refugee camp in Lesbos today as dozens of new arrivals were attacked by a mob of Afghans wielding sticks.

Greece has witnessed a surge in migrant arrivals in recent days amid fears of worsening weather and closing borders inside Europe, the United Nations and Greek authorities said.

The UN refugee agency said it had registered a clear 'spike in arrivals' that left some 27,500 packed on Greek islands by Tuesday morning.

A high-ranking Greek police official told AFP that of the 8,000 people who landed in Greece on Monday, 5,000 crowded onto the already overwhelmed island of Lesbos.

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Ugly scenes: Violence erupted at an over-crowded refugee camp in Lesbos today as dozens of new arrivals were attacked by a mob of Afghans wielding sticks (pictured)

Punches thrown: Newly-arrived migrants were waiting to be processed at the increasingly overwhelmed Moria camp when tempers flared

Fighting: Sticks were used as weapons and punches thrown as thousands continued to arrive in makeshift rafts and boats to flee conflict in Iraq, Syria, Afghanistan and other countries

Newly-arrived migrants were waiting to be processed at the increasingly overwhelmed Moria camp when tempers flared.

Sticks were used as weapons and punches thrown as thousands continued to arrive in makeshift rafts and boats to flee conflict in Iraq, Syria, Afghanistan and other countries.

The Greek police official suggested the hike was 'due especially to milder weather, which makes the journey easier, and to the serious concern among refugees about the ongoing closure of borders in Europe.'

Meanwhile, in a sign of the worsening weather large groups of migrants have been pictured wrapped in blankets and huddling up warm by camp fires as they continue their journey across Europe.

Tension was building among hundreds of men, women and children as they remained stranded in cold and wet weather near the crossing border between Serbia and Croatia.

They were seen close to the village of Berkasovo in Serbia today, as they try to continue their journey north in their search for a better life in Western Europe.

In previous years, the numbers crossing the Mediterranean to Europe have dropped off sharply as winter approaches, but the International Organization for Migration said Tuesday that recent arrivals, averaging around 9,000 a day, far exceeded the summer peaks.

'We are alarmed at how much this is continuing through the cold weather,' IOM spokesman Joel Millman told reporters.

Unmanageable influx: Greece has witnessed a surge in migrant arrivals in recent days amid fears of worsening weather and closing borders inside Europe, the United Nations and Greek authorities said. It led to numerous scuffles breaking out

The UN refugee agency said it had registered a clear 'spike in arrivals' that left some 27,500 packed on Greek islands by Tuesday morning

Concern: A Greek police official suggested the hike was 'due especially to milder weather, which makes the journey easier, and to the serious concern among refugees about the ongoing closure of borders in Europe.' Migrants at the overcrowded camp are pictured

Scuffles: In previous years, the numbers crossing the Mediterranean to Europe have dropped off sharply as winter approaches, but the International Organization for Migration said Tuesday that recent arrivals, averaging around 9,000 a day, far exceeded the summer peaks

Brawling: Migrants at the increasingly overwhelmed Moria camp were waiting to be processed when fighting broke out (pictured)

Hungary has announced that closing its border with Croatia has been a great success in stopping migrants and refugees entering the country, but it has caused problems further down the Balkan route, forcing people towards the tiny EU nation of Slovenia

Millman suggested that people smugglers were rushing their business out of concern Turkey would soon start cracking down on them, following a recent agreement with the EU.

Greek newspaper Kathimerini quoted police sources hinting Turkey is allowing more departures to put pressure on the EU and improve its leverage in discussions with the bloc, but the high-ranking police source told AFP that was a 'hypothesis, which is not held by the authorities.'

Nineteen people have died crossing from Turkey to Greece in the past nine days. The Greek coastguard said five migrants, including a baby and two boys, had drowned while trying to cross the Aegean Sea on Sunday.

At least 3,135 people have died making perilous journeys across the Mediterranean this year, according to UNHCR.

Keeping warm: In a sign of the worsening weather migrants close to the border between Serbia and Croatia were seen wrapped in blankets

Battling the elements: Tension was building among hundreds of migrants today as they remained stranded in cold and wet weather near the crossing border between Serbia and Croatia. Children were also seen huddling next to make-shift camp fires to keep warm

Worsening conditions: Refugees were seen close to the village of Berkasovo in Serbia today, as they try to continue their journey north in their search for a better life in Western Europe

Keeping warm: Refugees wrapped in blankets can be seen peeking out of the window as a train arrives at a Croatian-Serbian border town

Migrants are seen surrounded by muddy blankets as they huddle together under a shelter near the border between Serbia and Croatia

The agency's spokeswoman Melissa Fleming warned that the surge in Greek arrivals was putting huge pressure on the country's meagre reception capacities.

She urged the EU to follow through on its commitment to boost 'hot spot' reception facilities in Greece and elsewhere to ensure it will be possible to push ahead with an EU scheme to relocate 160,000 asylum seekers within the bloc.

So far, only 19 asylum seekers have been relocated under the plan - from Italy to Sweden - and Fleming said she hoped transfers from Greece could soon begin.

One of the biggest challenges, she warned, was to convince refugees to accept transfers to countries other than top picks Germany, Sweden and Austria.

Afghan migrants ride on a raft as they approach the Greek island of Lesbos after crossing a part of the Aegean Sea from the Turkish coast

New life: Syrian refugees, including this man pictured carrying his daughter, also continued to arrive on the Greek island on Tuesday

Emotional journey: A Syrian refugee woman is pictured breaking into tears after arriving at a beach on the island of Lesbos on Tuesday

Thousands of migrants are continuing to arrive in makeshift rafts and boats to flee conflict in Iraq, Syria, Afghanistan and other countries