Description:Social media website footage shows what Syrian activists say was heavy fighting in Hama province. The footage shows grey smoke billowing from an old castle in Qalaat al-Madyaq against a backdrop of gunfire. In Syria's third largest city, the rebel stronghold of Homs, residents accused government forces of indiscriminate shelling. The British-based Syrian Observatory for Human Rights said 16 people were killed in clashes around the country, half of them in Homs.(1:25)