Ankara, Dec 9 (IANS): The killing of three Turkish soldiers in the southeastern province of Sanliurfa bordering Syria was due to the "mental breakdown" of a soldier rather than a terrorist attack, Turkey's Prime Minister Ahmet Davutoglu said Tuesday.

"It is apparent that it is a case of mental breakdown. Whatever it is, those who lost their lives on duty are our martyrs," Xinhua cited state-run Anatolia news agency as quoting Davutoglu.

The prime minister said the incident happened due to psychological tension in the aftermath of a telephone call or message.

Sanliurfa Governor Izzettin Kucuk told reporters that a soldier suffered a mental breakdown and killed two other soldiers before committing suicide.

Earlier Tuesday, private Dogan news agency reported that three soldiers of the Turkish Armed Forces who were guarding the border at Ceylanpinar town of Sanliurfa province near the Turkey-Syria border were killed by gunfire from Syria.