Explosions are heard in the distance… As Syrian rebels fight for control of a fortified barrier in the town of Khan Sheikhoun.<br/> <br />Forces loyal to Assad have held the town for most of the past two years.<br/> <br />Now rebels say they are preparing to overtake it.<br/> <br />The town straddles the western highway linking Damascus to Aleppo.<br/> <br />It's been one of many fronts contested by the Syrian army and rebels.
