BEIRUT (AP) — Turkish drone strikes in northeastern Syria on Wednesday killed at least three members of a local Christian force and wounded others, including civilians, a Kurdish official and a Syrian opposition war monitor said.

There was no immediate comment from Ankara. Turkey has been attacking Kurdish fighters in Syria for years but attacks on the fighters from the country’s Christian minority have been rare.

The force that was targeted, the local Christian Syriac police known as Sutoro, works under the U.S.-backed and Kurdish-led Autonomous Administration of North and East Syria.

Siamand Ali of the U.S.-backed Syrian Democratic Forces told The Associated Press that the Turkish drones initially hit three Suturo vehicles near the northeastern town of Malikiyah. When a fourth vehicle, a pick-up truck, arrived at the scene to retrieve the casualties from the strike, it also came under attack, he said.

The Britain-based Syrian Observatory for Human Rights, an opposition war monitor, said three Suturo police members were killed, as well as one civilian.

The Observatory said the attack was the latest of 65 such strikes so far this year in northeastern Syria that have killed 18 people, mostly Kurdish fighters.

Turkey often launches strikes against targets in Syria and Iraq it believes to be affiliated with the Kurdistan Workers’ Party or PKK — a banned Kurdish separatist group that has waged an insurgency against Turkey since the 1980s. Turkey says that the main Kurdish militia in Syria, known as People’s Defense Units, or YPG, is an affiliate of the PKK.

Turkey’s state-run Anadolu Agency however, reported on Tuesday that the Turkish intelligence agency, MIT, had killed a senior Kurdish fighter member in an operation in the northern Syrian town of Qamishli.

The report identified the woman operative as Emine Seyid Ahmed, a Syrian national, who allegedly went by the code name of “Azadi Derik.”

She reportedly joined the Kurdish Women Protection Units, or YPJ, in 2011 and allegedly planned a number of attacks against Turkish security forces as well as cross-border missile attacks targeting civilians in Turkey, Anadolu reported.