A civilian car in which the off-duty soldiers travelled and a vehicle used by the public servant were found abandoned on a road outside Lice town, near Diyarbakir, the largest city of the southeast, they said.

Witnesses reported seeing armed militants of the outlawed Kurdistan Workers' Party (PKK) stop vehicles on the road overnight.

A search operation, backed by helicopters, has been launched to hunt down the kidnappers.

The PKK, listed as a terrorist organisation by Turkey and much of the international community, has carried out reprisal abductions in the past.

The group took up arms for Kurdish self-rule in the southeast in 1984, sparking a conflict that has claimed some 45,000 lives.