Rebel rocket fire killed 13 people in the **rthern city of Aleppo on Friday, as troops launched an offensive on rebels in Daraa province of southern Syria, state media said. The Syrian Observatory for Human Rights also reported the bloodshed in Aleppo and said a large-scale army operation was underway in Daraa for control of hills held by rebels. State television said rocket fire by rebels on the government-held Ashrafiyeh district of Aleppo killed 13 people, including women and children, and wounded 17. The Britain-based Observatory said at least 16 people were killed, including six children, and 60 wounded in rocket fire by Islamist rebels.