In this image made from amateur video released by the Ugarit News and accessed Monday, July 2, 2012, black smoke leaps the air from shelling near Ali bin Abi Taleb mosque in Talbiseh, the central province of Homs, Syria. The head of the Arab League urged Syria's exiled opposition to unite Monday, saying they must not squander the opportunity to overcome their differences as Western efforts to force President Bashar Assad from power all but collapse. (AP Photo/Ugarit News via AP video) TV OUT, THE ASSOCIATED PRESS CANNOT INDEPENDENTLY VERIFY THE CONTENT, DATE, LOCATION OR AUTHENTICITY OF THIS MATERIAL