Investigators examining the links between Ahmet Yumuşak and the terror group are said to have discovered the 29-year-old talking with potential clients about the price of sex with refugees, Daily Man reports.
He allegedly recommended certain women to his 'customers', who were inquiring about paying for sex with young females fleeing the Syrian warzone for what they had believed to be the safety of Yumuşak's native Hatay region of southern Turkey.
Yumuşak's alleged crimes came to light after local detectives launched an investigation into an attack by ISIS militants on police officers in the Turkish town of Niğde in March last year.
11 people, including Yumuşak, have already been charged in connection with that attack, according to Turkish newspaper Hürriyet.
Investigating officers using wiretaps to investigate the case are said to have caught Yumuşak arranging for vulnerable Syrian refugee women to have sex with 'customers', even going as far as to make personal recommendations, saying: 'the 16-year-old one is terrific'.
The alleged people smuggler has since been charged with forcing underage girls into prostitution.