Opposition activists are claiming more than 500 people have died in weeks of Syrian government air strikes on the city of Aleppo. The Syrian Observatory for Human Rights says the dead includes 151 children. Syrian government helicopters have been hitting Aleppo with highly destructive barrel bombs –- oil drums filled with explosives and sometimes with nails or scrap metal. At least 25 people were reportedly killed on Saturday when government forces bombed a vegetable market. Meanwhile, the Assad regime has evacuated thousands of residents from the town of Adra amidst heavy clashes with rebel fighters.