A total of four PKK terrorists surrendered to security forces in Turkey's southeastern Şırnak province, the Turkish Armed Forces (TSK) said Thursday in a written statement.

The four terrorists reportedly fled PKK shelters in northern Iraq and laid down arms in Şırnak's Silopi district, the statement noted.

The TSK statement also gave information about counterterrorism operations conducted within Turkey's borders Wednesday.

Two improvised explosive devices (IEDs), 11 cylinders used in the production of IEDs belonging to the PKK terrorist group were seized in eastern Bitlis province, while five Kalashnikov rifles and 12 hand grenades were discovered during ground searches in southeastern Mardin province.

Founded in 1978, the PKK has waged a decadeslong bloody campaign against Turkey.

The PKK, which is listed as a terrorist organization by Turkey, the U.S. and the EU, resumed its armed campaign in July 2015 after a brief reconciliation period.

Since that time, the PKK has been responsible for the deaths of some 1,200 security personnel and civilians, including women and children, while more than 4,000 security personnel and over 2,000 civilians have been injured.