PKK fighters have stepped up attacks on Turkish army posts in the southeast in recent weeks, with warmer weather allowing them to leave their mountain hideouts.
However, the group rarely attacks naval targets.
The incident comes one day after Abdullah Ocalan, the jailed leader of the PKK, reportedly decided to abandon the group's efforts to reconcile with the Turkish government.
Six people were killed at the weekend amid continuing violence in the southeast.
Thousands of Turkish soldiers are currently engaged in large-scale manoeuvres against the PKK in the area, with operations taking place in the provinces of Hakkari, Siirt, Tunceli, Diyarbakir and Bingol.