At least seven people were killed and 20 wounded when a blast ripped through a bus in a central district of the Syrian capital. The Syrian Observatory for Human Rights said it was not immediately clear what had caused the blast in the Souq al-Hamadiyeh neighborhood of Damascus. Observatory director Rami Abdel Rahman said the bus was reportedly carrying Shiite Muslim pilgrims visiting religious sites in the capital. More than 200,000 people have been killed in Syria since the conflict started, and around half of the country's population has been displaced.