BEIRUT - At least 49 people were killed in demonstrations across Syria on Friday, a prominent activist said, the highest death toll in a single day since protests against the rule of President Bashar al-Assad erupted last month. "At least 49 people were killed. There are a lot of wounded and many people are missing. We believe there are at least 20 people missing, some believe they are dead," activist Ammar Qurabi said. He said most of the dead had been shot, and a few died after inhaling teargas.