Turkish security forces detained four South Korean citizens in a forbidden military zone on the Turkish-Syrian border on Thursday.

The South Koreans were reportedly journalists, and authorities did not reveal their full names. Soldiers at a border outpost in the southern city of Kilis caught the suspects.

Kilis is challenged by rampant smuggling activity and attempts by foreigners to travel to Syria or vice versa in order to join radical groups active in the country. As the conflict in Syria practically drove border towns of Turkey's southern neighbor into lawlessness, more and more people flock to the border for illegal activities.

Turkey closed its border crossings to Syria due to the deteriorating security situation and only occasionally opens them for Syrian refugees seeking to return home.