Turkey's government has repeatedly been criticized for the way that it has permitted fighters for the Islamic State, al-Qaida, the Nusra Front and similar terror organizations to transit the country relatively freely en route to Syria ever since the beginning of the civil war nearly eight years ago.

"They will also use Turkey in order to leave Syria," Metin Gurcan, a security researcher at the Istanbul Policy Center (IPC), told DW. That, he said, is why it is important for the Turkish and EU security services to work together.

"Getting across the country will become extremely expensive for them," Gurcan said. "Ankara needs to make sure that as few fighters as possible settle in Turkey." He emphasized that it was vital that this topic be addressed by the international parties active in Syria's civil war.

'An important point'

Turkish President Recep Tayyip Erdogan has repeatedly claimed that Turkey is fighting more than one terrorist organization in Syria: the Islamic State and the US-allied Kurdish People's Protection Units, or YPG, who were instrumental against IS in the region. In addition, he has said that Turkish police carry out frequent raids on potential IS members. There are no official figures on the number of suspects arrested.

In Turkey, the battle against IS and its former fighters is taking place in part before the courts. In 2014, IS carried out the first of its 13 attacks in Turkey in the central Anatolian town of Nigde. Three people died, and another eight were wounded. Nine attackers were found guilty, including Benjamin Xu, from Germany, Cendrim Ramadani, from Switzerland, and Muhammed Zakiri, from Macedonia.

"Back then, the attackers were not convicted of ‘membership in a terrorist organization,'" said Ali Cil, one of the attorneys for the victims. "We objected to this at the time, but our objection wasn't sustained."

Cil said there were also irregularities at the hearing. For example, the accused didn't appear in court in person; instead, they participated by video conference. He said the defendants' invoking of this right had had a negative effect on the adjudication process. "The accused didn't answer any of the judge's questions — not even when they were asked their names," he said. "Just once, one of them shouted ‘God is the greatest' (Allahu Akbar)."

Cooperation with IS?

IS carried out one of its bloodiest attacks on October 10, 2015, in Ankara, when a suicide bomber at a peace demonstration killed 102 people.

The lawyer Sevinc Hocaoglu represented the relatives of one of the victims. She said she and her colleagues only had limited access to the files. "For the most part, the investigations were withheld from us," Hocaoglu said. "They didn't reveal the network IS had built up in Turkey. The trials were only half-heartedly conducted. That's still the case."

The lawyer is making serious accusations. At the time, Hocaoglu said, there were IS offshoots in the Turkish city of Gaziantep, on the border with Syria. "There was no secret as to where IS had its cells, and it was also clear who was going in and out," she said. "If the court had taken the camera footage into consideration, it wouldn't have been a problem to track IS in Gaziantep. But that wasn't done."

Hocaoglu said recordings of telephone calls had proved that some of the convicted IS fighters had had contact with law enforcement. "How were these members of IS able to travel in and out of Turkey?" she said. "What was the role of the law enforcement officers? There was no further investigation into any of that."

The IPC's Gurcan said the topic of how to deal with former IS fighters must to be seen in a wider context. IS and groups like it have lost control of land they had taken in Syria, but, he said, the organization continues to have members in Iraq and Syria, where it remains a "social phenomenon."

Unlike the terrorist organization al-Qaida, which summoned only fighters, IS had called on members to bring their families, as well, to the "caliphate" they were meant to help establish. "What will become of the wives who stay behind — and the children?" Gurcan said.
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