After Hungarian police used water cannons and tear gas on hundreds of migrants Wednesday in a bid to force them back from its border with Serbia, charities and action groups are becoming increasingly concerned that Europe's authorities are losing control of refugee crisis.
Coverage of the violent scenes in Hungary showed tear gas being used against crowds of migrants, among whom were children and babies. The police said they had detained 29 people including a "terrorist" amid the clashes.
The Secretary General of the United Nations (UN) Ban Ki-moon said he was "shocked" by the actions by Hungarian police on Wednesday.
"I was shocked to see how these refugees and migrants were treated. It's not acceptable ... since they are the people who are fleeing the violence and persecution, we must ensure our compassionate leadership," he told reporters at a UN press conference Wednesday.
Hungary is fast-becoming a flashpoint for the migrant crisis in the European Union (EU) and is struggling to deal with the numbers of refugees. Last week, it asked for emergency assistance from the European Commission to provide tents, blankets and heating devices for migrants.
Thousands of asylum-seekers coming from Syria in the Middle East over recent days and weeks have tended to use the country as a conduit to reach Germany and other prosperous northern European countries.
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By closing its border with Serbia by erecting a razor-wire fence, thousands of migrants have decided to go westwards via neighboring Croatia instead. Police there estimated 5,000 migrants had entered the country so far, Reuters reported.
Hungary opposes proposals for the European Union to relocate up to 120,000 migrants (on top of 40,000 already agreed) that have mainly gathered in Greece, Hungary and Italy in order to ease the strain on these countries. Hungary and its eastern European neighbors oppose compulsory quotas, however, saying that they will attract more migrants.
The EU's border agency, Frontex, estimates that more than 500,000 migrants have arrived so far this year, although that number could be conservative as the refugee registration process appears haphazard.
Walls are no solution
As Hungary visibly struggles to deal with the mass of migrants in its territory, its actions also drew a carefully-worded rebuke from Europe, which needs Hungary on side to implement its proposals to relocate migrants.
European Commissioner for Migration, Dimitris Avramopoulos, tried to placate Hungary during a visit to the country Thursday.
"The situation is not easy. These are very difficult times for your country…But you are not alone. Hungary is not alone. These are also difficult times for your neighbours too. From Greece, to Croatia, to Austria - today's challenges are shared across Europe."
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He appeared to rebuke Hungary's actions too. "We will work collectively to protect the Union's external borders. You are doing your part in this work I know. You also know that we do not always agree with the means used," he said.
"Walls are temporary solutions. You have seen yourself that this only serves to divert flows or escalate tensions. Violence is not the solution either."
The majority of people arriving in Europe are Syrians, he said. "They are people in genuine need of our protection. There is no wall you would not climb, no sea you would not cross if you are fleeing violence and terror."
- By CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt. Follow us on Twitter: @CNBCWorld