Europe's embrace of the PKK terrorist group has apparently encouraged militants to attempt to cross into European Union member countries as Turkey boosts its anti-terror campaign.
Four terror suspects were captured on Turkey's borders with Bulgaria and Greece on Monday and Tuesday.
Security forces in the northwestern border province of Edirne were patrolling an area popular among illegal immigrants trying to cross into Europe on Tuesday when they spotted a group of Syrians.
When the migrants that were discovered near the border with Bulgaria were taken to a detention center, police found out three of them were actually Turkish citizens and were wanted for membership to the PKK terrorist group.
On Monday, a suspect with an arrest warrant for PKK membership was captured in Edirne's border with Greece.
The PKK, which launched a terror campaign in 1980s, has killed thousands since then in armed attacks, suicide bombings, and car bombings across Turkey.
After a brief lull to its activities a few years ago in the wake of Turkey's now scrapped "reconciliation process," the group resumed its attacks in 2015.
Since then, PKK militants have killed hundreds of security officers and civilians, especially in southeastern and eastern Turkey which hosts a large Kurdish population.
As the group expanded its urban attacks, Turkey launched a crackdown last year and managed to wipe out the PKK presence in most of the region.
The group still remains a significant threat with occasional terror attacks targeting security forces though intelligence reports show they lost a considerable amount of manpower thanks to the anti-terror operations.
Even though the PKK is designated as a terrorist group by European Union, states in the bloc are accused by Turkey of tolerating its presence and approving of pro-PKK rallies.
Between 2006 and 2016, Turkey has demanded the extradition of a total of 136 PKK terrorists from Germany. The German government agreed to hand over only three of them to Turkish authorities, the Ministry of Justice had announced.
Similarly, the extradition of 263 other terrorists, between 2007 and 2016, had been demanded from the entire EU and only eight of them were delivered.