A teenager was shot and killed in southeastern Turkey on Saturday in clashes between members of a Kurdish Islamist party and youths linked to the outlawed Kurdistan Workers' Party (PKK), security sources said.
The 15-year-old's death in the town of Cizre brought the number of people killed there in fighting between Kurdish groups to three. Two others were killed on Saturday in clashes between members of the Islamist Free Cause Party (Huda-Par) and youth groups linked to PKK.
The two groups are fierce rivals. Huda-Par draws support from sympathisers with Turkey's Hizbullah militant group, which fought the PKK in the 1990s.
Armoured police vehicles patrolled Cizre town centre, where shops were closed on Sunday.
Late on Saturday, unrest spread to the neighbouring town of Silopi, where two people were wounded when PKK-linked youths clashed with police, who fired water cannon and tear gas.
Thirty-five people died in early October after Kurds rioted in several southeastern cities over what they saw as the government's refusal to help fellow Kurds fighting Islamic State in the town of Kobani across the border in Syria.
The violence, the worst in that part of Turkey in many years, was accompanied by intense clashes between PKK sympathisers and Islamist Kurds.
Calm in the region is key to a shaky peace process in which the government is negotiating an end to a 30-year insurgency with the jailed leader of the outlawed PKK, who called a ceasefire last year.
Prime Minister Ahmet Davutoglu described the incidents in Cizre as provocations. "We are determined to take all measures against provocateurs who try to disrupt public order," he said.