A roadside bomb, believed to have been planted by Kurdish militants, wounded four civilians in southeast Turkey on Sunday, security sources said.

The victims' car struck the bomb on the road between Sirnak and Cizre, a town close to Turkey's border with Iraq and Syria. Police also found a remote-controlled bomb on another road running north from Sirnak, and destroyed it with a controlled explosion.

Roadside bomb attacks are common in the southeast, where militants from the Kurdistan Workers Party (PKK) have waged a separatist insurgency that has claimed over 40,000 lives since it first erupted in 1984.

On Saturday, a female suicide bomber killed three people and wounded around 20 in Bingol, a town also in the mainly Kurdish southeast. The blast occurred at a tea house close to the office of the ruling AK Party in the town's main street.

No group has claimed responsibility for that attack.

Turkey, the European Union and the United States list the PKK as a terrorist organisation.