Damascus, July 4 (IANS): An explosion at a rebels' meeting in Syria's northwestern province of Idlib killed 31 of them, a monitor group reported on Saturday.

The blast took place in a mosque in the city of Ariha in the southern countryside of Idlib on Friday, while rebels of the Al Qaida-linked Nusra Front and an allied jihadi group were having Iftar, the fast-breaking meal in the Muslim holy month of Ramadan, according to the Syrian Observatory for Human Rights (SOHR).

The Britain-based watchdog group said the toll is expected to rise as many of the wounded are in grave condition.

The group, which relies on a network of activists on the ground, said the people behind the explosion are still unidentified.

Separately, the Jaish al-Fatah group, a coalition of several jihadi groups -- mainly the Nusra Front -- executed eight people in Idlib on charges of being spies for the Syrian government forces, Xinhua news agency reported.

The Nusra Front and like-minded groups captured the city of Idlib on March 28 and followed their assault with other offensives that gave them control of much of the province's countryside near Turkey.