At least one killed, 25 injured in car bombing in Syria's Azaz

A blast killed at least one person in a region of north Syria controlled by Turkey-backed Syrian opposition groups, a witness and a war monitor said on Saturday.

The explosion in Azaz was caused by a car bomb, said the war monitor, the Syrian Observatory for Human Rights. The blast hit a sit-in to demand new elections to the local council, the witness said.

The Observatory said one person was killed and others injured. The witness said two were killed and 25 injured.

Azaz is about 20 kilometres from Aleppo and 100 km from Idlib where the Syrian regime is expected to launch an operation to regain control.

Turkish military action in Syria

Turkey has launched two military operations in northern Syria since 2016 in support of the opposition fighting regime leader Bashar al Assad. Turkey's military action lead to its control over a zone along the border.

It took that territory after offensives against the two terror groups that previously controlled it: Daesh and the PKK's Syrian affiliate, YPG.

Ankara has brought together some of the opposition groups it backs there into a unified armed force, which it trains and pays. 

Northern Syria has become a haven for large numbers of displaced people who have sought refuge from fighting elsewhere in the country, or who do not want to live under Assad.

Damascus has mobilised forces for an expected offensive on the adjacent opposition and rebel-held area in and around Idlib province, which humanitarian agencies have warned could spark a new flood of displacement towards the border region.