Ten prisoners from each side were exchanged.
Syria regime and rebels swap prisoners, Turkey says
The Syrian government and rebels swapped prisoners Saturday in a "first important step" in building trust between the warring sides under a Russia-Iran-Turkey-brokered peace process, Turkey's foreign ministry said Saturday.
"Certain individuals" were exchanged simultaneously in northwest of Syria, near the town of Al-Bab close to Aleppo, the ministry said, calling it a "pilot project".
While it did not give a precise figure of detainees involved, the British-based Syrian Observatory for Human Rights, which relies on sources in Syria, said 10 prisoners from each side were exchanged.
Russia, Iran and Turkey are working to bring about peace in Syria under what is known as the Astana process.
Each country plays a key role in the conflict that started in March 2011. Russia and Iran have intervened on the side of Syria's government, ensuring its survival, while Turkey supports rebel groups in northern Syria to prevent Syrian Kurds establishing and expanding territory along its border.
All of them say they are fighting Islamic State fighters and other extremists in the northern regions.
Turkey of late has become quieter about its initial stated aim of seeing Syrian President Bashar al-Assad leaving power as it has stepped up cooperation with Russia over Syria.
In September, Turkey and Russia agreed to set up the buffer zone to avert a Syrian regime offensive, but jihadists who hold around 70 percent of the area have refused to withdraw.
The Astana process has gradually come to eclipse a UN-sponsored negotiations framework known as the Geneva process whose participants include the United States and European powers that would be key donors in an international post-conflict reconstruction programme for Syria.
Obstacles to securing Western reconstruction aid include an insistence by the US and EU on a transition that would see Assad go, as well as the presence of Iranian and Iranian-commanded fighters in Syria.