An Iranian-made unmanned aerial vehicle participated in an attack on Turkish troops operating in Syria that left four dead and 10 wounded in late November, a senior Turkish government source told the Turkish press on Wednesday. The attack took place just two days before Turkish Foreign Minister Mevlut Cavusoglu and Hakan Fidan, head of the country's MIT intelligence agency, made a surprise visit to Tehran on November 26. Cavusoglu denied on Wednesday that his visit dealt with the drone incident, claiming that the talks with Iranian officials covered ways of ending the crisis in Syria and sending humanitarian aid. Russian Foreign Minister Sergei Lavrov had said earlier that it had been made clear to him that no Russian manned or unmanned aircraft was operating in the airspace in question. Meanwhile, a Turkish soldier was killed and six others were wounded on Wednesday when an ISIS car bomb blew up in the city of Al-Bab in northern Syria.