Members of a Syrian rebel group were targeted in the attack at a village east of Saraqeb in Idlib province.
At least 23 members of a Syrian rebel group were killed on Sunday in two bomb attacks in Syria's Idlib province.
Britain-based Syrian Observatory for Human Rights said two blasts hit the headquarters of Ahrar al Sham rebel group in a village east of Saraqeb in Idlib province.
Ahrar al-Sham said in a statement a lone attacker had driven a motorbike up to the building, detonating explosives attached to himself and a bomb on the bike at the same time, killing and wounding dozens of rebels.
It blamed Daesh for the attack.
Unverified photos on social media showed bloodied corpses and a blackened motorbike outside a small building in the village.
Idlib is a rebel stronghold, but some factions have fought among themselves this year, including in clashes that pitted groups aligned with Ahrar al Sham against groups that joined the al Qaeda-linked Hayat Tahrir al Sham alliance.
Syrian regime forces have taken advantage of rebel infighting, particularly a separate spat further south near Damascus, to recapture territory from rebels in the six-year conflict.