Car bombs killed at least eight people including three children in two separate incidents Sunday in northern Syria, a war monitor said.

One blast hit a car repair shop in Shawa, a village near the Turkish border held by pro-Ankara fighters, residents told AFP.

Five civilians including three children were killed and 10 others injured, the Britain-based Syrian Observatory for Human Rights said.

Areas held by Turkey and its Syrian proxies in northern Syria are the scene of regular targeted killings, bombings and clashes between armed groups.

In the second incident, an explosive device planted in a vehicle killed three fighters affiliated with the Kurdish-led Syrian Democratic Forces (SDF) in the city of Manbij, according to the Observatory.

Manbij is a former stronghold of the Islamic State group that is now held by a military council affiliated with the US-backed SDF.

There was no immediate claim of responsibility for the bombings.

Syria's war broke out in 2011 with the brutal repression of anti-government protests.

It has since evolved into a complex conflict involving jihadists and foreign powers, and has killed more than half a million people and displaced millions.