NEW : At least 79 people killed Saturday , opposition group says . Rebels go after government air bases one by one in the north . Syrian troops cut off food , medicine and ammunition to rebels in Damascus . Opposition and government sources report that the extremist al-Nusra Front , which the United States has designated as a terrorist group , is taking part in the assault on Taftanaz . Score: 6
NEW : At least 79 people killed Saturday , opposition group says . Rebels go after government air bases one by one in the north . Syrian troops cut off food , medicine and ammunition to rebels in Damascus . Score: 6