Hundreds of refugees living in poor conditions in the Serbian capital are refusing to go into official camps, fearing it will lead to their deportation.

For Akbar, injured and threatened by the Afghan Taliban, who claims to have had his nose broken by the police in Croatia and his arm broken by the police in Bulgaria, deportation is a constant worry.

"They have deported many people from Bulgaria," he said. "We are scared. If they deport us to there, Bulgaria will deport us back to Afghanistan."

Thousands of Afghans and Pakistanis have been deported en masse from countries in Europe.

In Serbia, hundreds were rounded up and moved back to the border with Macedonia.

READ MORE: Concern over EU plans to send refugees back to Greece

At the same time, the Serbian government has told charities and other help groups that they cannot operate in the refugee camps.

The United Nations has condemned European countries for what it is calling a policy of "pushback".

Hans Friedrich Soder of UN's refugee agency, UNHCR, said: "It is not in line with the international and European law.

"It should not happen, especially in this winter conditions, because it puts the refugees at heightened risk of being harmed by the cold weather."

The Serbian government said it will deport the refugees.

However, other countries, including Germany, have done, so trust is in short supply.