Some 300 to 400 refugees stranded along Serbia’s borders have camped out in the area amid biting wind and freezing temperatures.
Refugees were huddling around small fires in an abandoned factory near Croatia's border on Monday as aid groups tried to distribute food and warm drinks. Some 4,000 other are accommodated in asylum centers.
Humanitarian workers said the refugees were in dire situation and authorities had effectively abandoned them.
“These people continue to stay outside in very inhumane and unsafe conditions ... There is no clear access to water or sanitation facilities,” said Andrea Contenta, an adviser in Serbia for the international medical charity Doctors Without Borders, also known by its French acronym MSF.
Contenta rejected claims that a flow of refugees along the Balkan route had completely stopped, saying refugees were still traveling on the route, which is leading from Turkey to Greece or Bulgaria, and on to Macedonia and Serbia.
“We cannot continue to say that the Balkan route is closed ... We have to acknowledge that people are still (moving) along the Balkans,” he said, adding that European authorities had to find a solution to avoid putting more lives at risk.
The European Union and Ankara reached an agreement in March last year to relocate all refugees landing on Greece’s shores from Turkey.
That caused a massive and historic influx of refugees into Europe to subside dramatically, although scores of refugees still dare the risky journey in the hope that they move on to wealthy countries in Western and Northern Europe. Countries on the Balkan route have also imposed heavy restrictions on the movement, making it more difficult for refugees to take the route.
Refugees that make it to Serbia have the daunting task of crossing into the EU countries of Croatia and Hungary as police normally push them back to Serbia.