The Grand Mosque in the holy city of Mecca  is the world's largest and houses the Kaaba, a multibillion-dollar project was going on there to enlarge the mosque, and so the site is currently ringed with cranes. On Friday, a large construction crane toppled over and crashed into the Grand Mosque, killing at least 107 people. As per reports available from Saudi Arabia the governor of Mecca province, prince has called for an investigation into the cause of the crane collapse.