The soldiers were on foot as part of an operation pursuing Kurdistan Workers Party (PKK) guerrillas near the Iraqi border when an explosive device, most likely a homemade bomb, detonated, the officials said on condition of anonymity.

In a separate incident, a PKK fighter in the province of Kahramanmaras was killed late on Tuesday during a clash with Turkish soldiers, the officials said.

Security forces are carrying out large-scale operations in several provinces in the mainly Kurdish southeast.

The spring thaw in the mountainous area is traditionally when violence picks up in the 25-year conflict between the PKK and the Turkish army that has killed some 40,000 people, mainly Kurds. Fighting has dropped sharply since the 1999 arrest of PKK leader Abdullah Ocalan.

The PKK has dropped its initial demand for an independent homeland and says it seeks autonomy for the southeast and more cultural and political rights for Turkey's estimated 14 million Kurds. The group has said violence could rise after a pro-Kurdish party in parliament was banned for links with the outlawed rebel group.