Opposition activists have posted a video purporting to show at least 51 muddied male bodies alongside a river bank in the rebel-held Bustan al-Qasr neighbourhood of Aleppo.
The video, which is too graphic to post, follows a man walking along a river bank past dozens of male bodies with their hands tied and blood coming from their heads.
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The government is encouraging motorists to think twice about buying diesel cars in a bid to improve air quality.
Atlantic frontal systems spread rain in from the northwest on both weekend days. Windy - with gales across the north and west but mild.
The band announced at a free concert on Friday that they would take over the event's Pyramid stage on Saturday June 25.