An explosion hit the vehicle of a rebel commander in the Syrian city of al-Bab in the northern countryside of Aleppo Province on Thursday, a war monitor reported.
The commander was injured in the blast ripping through his vehicle, said the Syrian Observatory for Human Rights.
The bombing is part of the rampant lawlessness and chaos in areas controlled by the Turkey-backed rebels in the countryside of Aleppo, the London-based watchdog added.
A day earlier, at least 10 people were wounded when a booby-trapped motorcycle exploded in the city of Jarablus, which is controlled by the Turkey-backed rebels near the Syrian-Turkish border in northern Aleppo.
Explosions and assassinations have become daily occurrences in areas controlled by the Turkey-backed rebels in northern Syria, according to the Observatory.