Beirut -- A Syrian human rights group says at least 42 people have been killed across Syria -- many of them villagers who tried to approach the besieged southern city of Deraa. Human rights activist Mustafa Osso said the death toll could rise. He is the head of a human rights group based in Syria, which compiles death tolls from the crackdown. Thousands of people took to the streets across the country Friday, calling for President Bashar al-Assad's downfall and pledging support for the citizens of Deraa. Deraa is at the heart of the country's six-week uprising. The regime has unleashed the army, backed by tanks and snipers, to crush the protest movement.