Turkey ramped up efforts against the militant Kurdistan Workers' Party, known by its Kurdish initials PKK, following a series of high-profile attacks in the Kurdish south of the country. Turkish lawmakers early this year backed a measure permitting cross-border raids into northern Iraq to strike PKK targets there.
Turkish lawmakers have complained that the PKK is simultaneously launching a terrorist campaign in Turkey while seeking favors from European countries.
Suleyman Ozeren, an associate professor at the Turkish National Police Academy, told Turkish daily newspaper Today's Zaman that Germany's tolerance for Kurdish separatist groups complicates Ankara's counter-terrorism efforts.
"We do not see the German government taking effective measures to make it difficult for the terror organization to raise money or recruit new militants," he said. "The country has turned out to be the best place for the PKK to run terror propaganda openly and without any difficulty."
Washington, Iraq and Turkey are among the countries that have designated the PKK a terrorist organization.