A top Syrian rebel leader and head of the most powerful insurgent group in the eastern suburbs of Damascus was killed in an aerial raid on the group's headquarters, rebel sources and the Syrian army say.
The death of Zahran Alloush, 44, head of Jaysh al Islam, is a blow to rebel control of the rural eastern suburban area of Damascus known as al Ghouta, the rebels said.
Defence experts say the disarray among the rebel forces could also consolidate the control of Syrian President Bashar al-Assad over the rest of the area.
Several rebel leaders have been killed since Russia began an aerial campaign on September 30 in support of its ally Assad, although Moscow has insisted it is concentrating its attacks on Islamic State.
The rebel sources said that in the raid Russian planes fired at least 10 missiles at a secret headquarters of the group, which is the largest rebel faction in the area and has up to 20,000 fighters, according to Western intelligence.
The Syrian army said Alloush was killed as the result of intelligence on the ground. Rebels blamed Russian sophisticated spying planes which they say rarely leave their skies.
A rebel source said the group had chosen one of its top military commanders, Abu Hammam al Buwaidani, as the new head.
The rebels said Alloush was killed while holding a meeting with other rebel leaders in the Marj area of al-Ghouta, which has been the target of a major Syrian assault in the last few weeks.
Jaysh al Islam will be part of a negotiating team expected to hold talks with Assad's government in Geneva.
Alloush, who was released by the Syrian authorities at the start of the conflict in 2011 when it let scores of Islamist detainees go free, had been criticised for a crackdown on dissidents in the areas he controlled.
Activists accused him of kidnapping several prominent figures.
Alloush was ideologically at odds with Islamic State and al Qaeda, espousing a more moderate brand of Islam. He fought against more militant Islamists and drove them out of his territory. He had dozens of jihadists locked up.
Syria has long accused Saudi Arabia of financing arms and other supplies to Alloush. But there have also been reports that while on regional visits to countries hostile to Assad's government including Turkey and Saudi Arabia, Alloush failed to win the support he wanted for his group.
