Turkey must rein in Syrian rebels it supports in northern Syria who may have carried out kidnappings, torture and looting of civilian property, United Nations war crimes investigators said on Tuesday.
The panel also said transfers of Syrian nationals detained by the opposition Syrian National Army to Turkish territory for prosecution may amount to the war crime of unlawful deportation.
In a report covering the first half of 2020, the U.N. Commission of Inquiry on Syria said assassinations and rapes of civilians by all sides, marked by "sectarian undertones", were on the rise in the conflict that began in 2011.
"In Afrin, Ras al Ain and the surrounding areas, the Turkey-backed Syrian National Army may have committed the war crimes of hostage-taking, cruel treatment, torture and rape," panel chair Paulo Pinheiro told a news briefing.
"Turkey should act to prevent these abuses and ensure the protection of civilians in the areas under its control," he said.
Turkey's Defence Ministry says it goes to great lengths to avoid civilian casualties during military operations in Syria.
Ankara and Moscow back opposing sides in Syria. Russia, along with Iran, supports President Bashar al-Assad's forces and Turkey backs rebels trying to oust him. Turkey seized control of the border town of Ras al Ain last year in an offensive to push back Syrian Kurdish YPG fighters, which Ankara views as a terrorist group.
Turkey wields influence as it funded, trained and allowed the rebel force known as the Syrian National Army to enter Syria from Turkey, panelist Hanny Megally said.
"Whilst we can't say Turkey is in charge of them and issues orders and has command control over them, we think that it could use its influence much more to bring them into check and certainly to pressure them to desist from the violations being committed and to investigate them," he said.
Investigations carried out so far by the Syrian National Army are insufficient, even as violations increase, he added.