"People have to drop what they are doing and come here to help refugees because this is a humanitarian problem," Czech volunteer Juracz tells IBtimes UK while he assists refugees waiting for the Berkasovo-Bapska crossing point in Serbia to open, so that they can cross into Croatia.

Serbia is merely a transit point for refugees, who usually spend less than 24 hours in the country. However, when authorities temporarily close crossing points due to security issues or to stagger the refugee influx, thousands of people, including pregnant women and children, sleep in makeshift camps in the freezing cold.

Juracz explains that refugees are allowed to cross the border only in groups of 50. "Sometimes two or three buses come at the same time and refugees have to wait for their turn," he says.

"Before people were calm but then something happened and all stood up and started pushing even if the border was still closed. They are very nervous, in the tents we have rooms where we play music and try to make them relax, but sometimes they become impatient."

Juracz explains that some volunteers from the Czech Republic go to the crossing borders in Serbia at the weekends as they do not have other commitments – such as education or work – that hold them back. However, he warns that more has to be done.

"I am skipping school to be here for a week because there are not enough volunteers during weekdays," he says. "The amount of refugees is not lower during the week.

"Even if I might not agree with the way we are handling this in Europe, the conditions people are going through here are inhumane. We have to come here and help for humanitarian reasons."

IBTimes UK travelled to Serbia courtesy of World Vision UK. Click here for more information about the World Vision UK refugee crisis appeal.

In Focus: Migrant crisis continues on Serbian border IBTimes UK