Kelebija, Serbia - After Serbian police raided the impromptu camp hugging the Serbian-Hungarian border, many of the hundreds of refugees and migrants previously camping in a sparsely populated area moved elsewhere.

Yet, the nearby Kelebija border crossing remains their last hope of entering the European Union through Hungary, an increasingly difficult point of entry due to the barbwire fence that spans the border.

Food scraps, old cans, abandoned clothes, plastic cutlery and other rubbish is scattered among the trees and bushes on the border.

According to Danijela Korac-Mandic of the Novi Sad Humanitarian Centre, a group that provides food and other assistance to refugees and migrants in the area, Serbian police raided the area on Wednesday.

They packed three buses with refugees and migrants who had not registered with Serbian authorities and dismantled their tents before sending them to the Presevo reception centre.

Among the 150 asylum-seekers remaining in the area are many who escaped from the police raid and have taken refuge in nearby forest, barns and an abandoned duty-free shop. Others sleep in tents near the already crowded Subotica reception centre and a bus station.

READ MORE: Stranded and sick, refugees endure harsh Serbian winter

The United Nations refugee agency, the UNHCR, estimates that more than 6,400 refugees and migrants are stranded in Serbia due to border closures across Europe.

The Serbian government's Commissariat for Refugees and Migrants released a statement claiming that every refugee and migrant will find shelter, especially as the winter weather grips the region and temperatures plummet to as low as minus 20C.

Across the border, the Hungarian Homeland Security chief adviser Gyorgy Bakondi said in statement that a growing number of refugees are trying to enter Hungary. He also blamed NGOs for "providing misinformation" and claimed humanitarian groups spread the rumour that the borders were open.

The Hungarian government, which deployed 500 new border police officers, has also announced plans to detain all asylum-seekers until their applications are processed.

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