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 ISIS 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 extremists and foreign powers, and has killed more than half a million people and displaced millions.