"As a result of a clash with terrorists in the area of the Claw-Lock operation, three of our soldiers were killed and four soldiers were injured," the ministry said in a statement.
In April, Ankara launched the Claw-Lock operation against PKK militants, which are designated as terrorist by Turkey, in the northern part of Iraq, using special forces and military aviation. Iraq has criticised the step as posing a threat to its national security, while Turkey has said the operation is prompted by the need to secure the country's borders.
The Turkish government has been fighting the PKK, which wants to establish a Kurdish autonomy in Turkey, since the early 1980s. The PKK and Turkey signed a ceasefire agreement in 2013, but it collapsed just two years later over several terrorist attacks which Ankara blamed on the Kurds.
The Turkish armed forces have been seeking to destroy PKK military bases located in the northern part of Iraq. According to Turkish President Recep Tayyip Erdogan, around 6,000 PKK members have been killed in Turkey and 6,900 outside the country since July 2015. During the same period, Turkey lost over 1,200 soldiers in clashes with the PKK.