Situated in the northern part of Syria, the Idlib province saw 25 Al-Nusra fighters killed when a bomb exploded in a mosque on Friday, said a monitoring group.
"Twenty-five members of Al-Nusra Front, including a leader of the jihadist group, died in an explosion inside a mosque in the city of Ariha, in Idlib province," Rami Abdel Rahman, head of the Syrian Observatory for Human Rights was quoted by AFP as saying.
Hundreds of Syrians had reportedly been summoned for an Iftar (an evening meal to end Ramadan passed) in the Salem mosque in the city of Ariha, the agency reported.
The cause of the blast has not been revealed yet.
Idlib province, with a population of 165,000, has controlled mostly by Al-Nusra Front since April.
Civil war in Syria ongoing since 2011 has brought 230,000 deaths, as jihadists, government forces and rebels continue to fight each other.
