ISLAMABAD - An over-speeding bus allegedly belonging to WAPDA hit former federal secretary of ministry of finance, Habibullah, and his wife to death on Wednesday.According to police, incident occurred here at Sector G-10. Both husband and wife were critically injured and rushed to PIMS where both succumbed to injuries. The driver of bus, according to police, managed to flee. Islamabad police impounded the vehicle and registered a case against the driver.