"An image grab taken from a video uploaded on YouTube on June 11, 2012 shows smoke billowing from the flashpoint Syrian city of Homs which activists said was being attacked by regime forces. UN-Arab League envoy Kofi Annan said he is gravely concerned by increased fighting between Syria's troops and rebel forces as violence killed dozens of people across the country. AFP PHOTO/YOUTUBE  == RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT ""AFP PHOTO / HO / YOUTUBE"" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS - AFP IS USING PICTURES FROM ALTERNATIVE SOURCES AS IT WAS NOT AUTHORISED TO COVER THIS EVENT, THEREFORE IT IS NOT RESPONSIBLE FOR ANY DIGITAL ALTERATIONS TO THE PICTURE'S EDITORIAL CONTENT, DATE AND LOCATION WHICH CANNOT BE INDEPENDENTLY VERIFIED  ==-/AFP/GettyImages Photo: -, AFP/Getty Images"
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