The separatist group, known by its Kurdish initials PKK, announced it would abandon Turkey starting in May, as part of a settlement process between jailed PKK leader Abdullah Ocalan and the Turkish government.
The formal withdrawal process started May 8.
Huseyin Celik, deputy leader of the ruling Justice and Development Party, said the PKK was causing trouble in southern Turkey as it moved out of the country.
"The PKK has kidnapped many people since the cease-fire between the Turkish military and the PKK started," he was quoted Friday as saying by Turkish newspaper Today's Zaman.
The PKK did not disarm as part of the settlement. The group said it was frustrated it did not get security guarantees under the terms of the settlement.
Pro-Kurdish leaders said PKK members were attacked during previous peace initiatives.
The European Union said it views the Kurdish initiative as a boost to integration efforts with Turkey.
The government said a small fraction of the PKK fighters have left Turkey, though pro-Kurdish officials dispute the government's claims.
Ankara said it expects most of the active fighters will be out of the country by the end of the year.