At least 13 civilians were killed when a car bomb exploded in a northern Syrian town close to the country's border with Turkey on November 2, Turkish officials said.
At least 20 people were injured in the blast, which occurred near a market in the northeastern town of Tal Ayab.
The London-based Syrian Observatory for Human Rights reported that 14 people were killed and that some of the victims were Turkish-backed militiamen.
The Turkish Defense Ministry blamed the attack on the Syrian Kurdish People's Protection Units (YPG) militia, which Ankara has labeled a "terrorist" branch of the outlawed Kurdistan Workers Party (PKK).
As part of a deal struck on October 17 between Turkey and the United States, a 120-kilometer "safe zone" was established between the towns of Tal Abyad and Ras al-Ain, and the YPG was obligated to withdraw from the area.
On November 1, Turkey and Russia began joint military patrols to monitor the withdrawal and enforce the "safe zone."
Turkey launched an offensive against the YPG in northern Syria last month after the United States withdrew its forces from the area.