Hungarian Prime Minister Viktor Orban said on Saturday there was a clear link between illegal migrants heading to Europe and a rising threat of terrorism, justifying his conservative government's tough anti-immigration stance, Reuters reported. The landlocked central European country is part of Europe's visa-free Schengen zone, making it attractive to migrants coming through the Balkans. It has registered more than 80,000 migrants so far this year, nearly double the number in all of 2014. Most are from poor or conflict-ridden countries like Syria, Afghanistan and Iraq, looking to move on to wealthier western Europe. Hungary plans to complete a four-metre-high (12 feet) fence along its border with southern neighbour Serbia by November to stem the flow of migrants. The plan has drawn criticism from Serbia as well as the United Nations' refugee agency.