BEIRUT (Reuters) - Turkey’s military shelled Syrian government forces and their allies on Thursday, causing deaths and injuries, Syrian state media quoted a military source as saying.

State-run SANA news agency quoted the military source as saying that the Turkish bombardment targeted Syrian border guard positions in the countryside near the northern city of Manbij.

Turkey intervened in northern Syria in August in support of rebel groups with the twin goals of driving Islamic State from its border and preventing Kurdish groups from building an autonomous zone along the frontier.

Ankara is particularly concerned about the Syrian Kurdish YPG militia which it regards as an extension of the Kurdistan Workers Party (PKK), which has fought a three-decade insurgency inside Turkey.

The area around Manbij has been controlled since last year by the Manbij Military Council, a local militia that is a part of the Syrian Democratic Forces (SDF), an umbrella organization of armed groups of which the YPG is also a part.

The United States, which supports the SDF in its fight against Islamic State, and is also an ally of Turkey, has said it has taken steps to try to prevent conflict between the two sides.