The suspect, Mehdi A., is said to have travelled to Syria three years ago with his wife and two toddlers, to join IS. He was on an international list for most wanted people compiled by Europol. In Belgium, he has a police record connected to terrorism.
The arrest is said to have happened in the Istanbul district Fatih. Police followed the man using CCTV footage and found out where he was living. The suspect may be extradited to Belgium, but this has not been arranged yet. Turkish media claim he had plans for a terrorist attack in Istanbul. He may also be connected to terrorist attacks in Europe.