Greece wants to build a fence to stem illegal immigration across the Evros river at the Greek-Turkish border. The EU is negotiating with Turkey about a repatriation agreement.Ever since the EU border agency Frontex has been controlling the eastern Aegean, more and more people have been trying to enter the EU via Greece's land border with Turkey. The Evros has been the scene of tragedies as desperate migrants attempt to cross the river. Some have drowned, others have been killed or injured by mines. We met in Istanbul up with a young man from Sudan waiting for his family to send him money to pay a human trafficker.