Istanbul, Sep 21 : Turkish security forces have detained 19 illegal Afghan immigrants in country's biggest city Istanbul, local media reported. Istanbul municipal police units on Monday stopped a van on suspicion in the Sultangazi district on the European side of the city, according to report by the Demiroren news agency. The teams found the immigrants jammed inside the vehicle and informed police forces, Xinhua news agency quoted the report as saying. These immigrants have reportedly tried to go to the northwestern border province of Edirne, some 240 km away from Istanbul, to cross into Greece. Turkey, a key transit point for asylum seekers on their way to Europe, has been increasingly witnessing an influx of Afghan refugees fleeing the country following last month's takeover by the Taliban. The country hosts more than 4 million refugees, including 3.6 million Syrians, within its borders, mostly in Istanbul. /IANS