Thousands of refugees have been stuck in swamp-like conditions between Serbia and Croatia, after Croatian authorities barricaded their border. The UNHCR says up to 2,500 people were stuck in the border region of Berkasovo and Bapska on 19 October.
Iroda Asqarova, a UNHCR Coordinator, said: "We are distributing raincoats, we are distributing blankets, we are distributing biscuits and water. We are doing as much as we can, and the other organisations are the same. The Doctors (Without Borders) are receiving many, many medical cases.
"As you can see this is a serious humanitarian situation. If you go to the crowd you will see women with children, with disabled people, they are all trapped and the border at the moment remains closed from Croatian side."
Croatian police have barricaded their side of the border, meaning hundreds of refugees have been forced to wait in the rain to cross into the country. People were seen gathering around camp fires, huddling in the tents and seeking shelter in a dilapidated shack.
It is believed that up to 5,000 people are crossing into Serbia and Macedonia from Greece and other neighbouring countries. The European Union (EU) has agreed a plan to share out 120,000 refugees among the member states.
This plan has been opposed by many EU countries, including Hungary. The International Organisation for Migration estimates 700,000 people will cross into Europe from the Middle East, Africa and Asia this year.