Clashes broke out between Hungarian riot police and migrants trying to break through the country’s closed border with Serbia on Wednesday.

Hundreds of people gathered at the closed border crossing near Horgos in Serbia and pelted Hungarian police on the other side of the border in Roszke with plastic water bottles and stones.

They demanded that Hungarian authorities let them enter the country from where to proceed north to wealthier countries of the EU’s borderless Schengen zone such as Austria and Germany.

Hungarian policemen arrest a migrant at the border crossing into Hungary, near Horgos, Serbia, Wednesday, Sept. 16, 2015. Photo AP/BTA

Hungarian police in full riot gear deployed armoured vehicles and used tear gas and water cannons to repel the people massed on the other side of the border.

At least 20 Hungarian police officers and two children were injured in the clashes, Reuters reported.

Hungarian police use tear gas at the "Horgos 2" border crossing into Hungary, near Horgos, Serbia, Wednesday, Sept. 16, 2015.  Photo AP/BTA

Hungary closed its entire southern border with Serbia on Tuesday, putting into force new laws that make it illegal to enter the country or damage a new razor-wire border fence. Hungarian courts have started fast-track of arrested migrants, the BBC said.

Although the flow of refugees from southern Serbia was redirected to the north-west of the country towards the border with another EU member state, Croatia, during the night, around 1,000 refugees who had arrived at Horgos earlier were still refusing to abandon hope of entering Hungary on Wednesday, Serbia’s news agency Tanjug said.

Following the clashes between migrants and police, Hungary announced it is closing the Roszke-Horgos border crossing to all traffic for at least 30 days.

This picture taken by a drone shows the stranded migrants at the border crossing between Serbia and Hungary near Horgos, Serbia, Wednesday, Sept. 16, 2015.  Photo AP/BTA