At least 25 members of Syria's al-Qaeda affiliate, al-Nusra Front, including a leader, have been killed in a blast at a mosque in north-western Idlib province, activists say.
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The UK-based Syrian Observatory for Human Rights said that dozens more were injured in the city of Ariha
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People had been gathering at the mosque to break their Ramadan fast at the time, the group said
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The cause of the explosion is not yet known
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An unnamed senior non-Syrian member of al-Nusra was reportedly killed in the explosion at Salem mosque, according to the Observatory
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Ariha was one of the last government strongholds in Idlib when it was captured by rebels in May



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An Islamist coalition called the Jaish al-Fateh (Conquest Army), took control of the city after a rapid offensive, activists said
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Rebels had earlier claimed a number of cities in the province, including Idlib and Jisr al-Shughour
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The fall of the Ariha left most of Idlib province, bordering Turkey, in rebel hands
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Al-Nusra is among 13 Islamist groups that came together on Thursday to launch a massive assault on the northern city of Aleppo
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More than 230,000 people are believed to have been killed in Syria since the uprising against President Bashar al-Assad began in March 2011.
Some 11.5 million others - more than half of the country's population - have fled their homes.