Hungary's military has begun building a fence on the country's southern border with Serbia, meant to stem the unprecedented flow of migrants.

State news wire MTI says work on the fence started Monday morning on the outskirts of the town of Morahalom, where a bulldozer was preparing the ground for construction. Foreign Minister Peter Szijjarto had said earlier the 4-meter (13-foot) high fence would be built in the eight to 10 areas "most exposed to the immigration pressure."

Around 80,000 migrants and refugees have reached Hungary already this year. Currently about 80 percent of them are from war-torn countries like Syria, Iraq and Afghanistan.

Most request asylum but quickly go to other, wealthier European Union countries like Germany and Sweden before their requests are settled.