The incident occurred near a military outpost in Tatvan town, Bitlis province, as a vehicle carrying the soldiers went by, the source added.

The vehicle was overturned by the impact of the explosion.

The blast was believed to be the work of rebels from the Kurdistan Workers' Party (PKK), which often plants home-made explosive devices on roads used by the army.

Some 45,000 people have been killed since 1984 when the PKK took up arms against Ankara for self-rule in the mainly Kurdish southeast of the country.

The group is considered a terrorist group by Turkey, the United States and the European Union.