A damaged bus is seen at the site of a blast near a new museum being built close to the Giza pyramids in Cairo, Egypt May 19, 2019. REUTERS/Sayed Sheasha  NO RESALES. NO ARCHIVES
Officials examine the damaged tourist bus after a blast near a museum being built close to the Giza pyramids in Cairo on May 19, 2019. Reuters

Giza attack reveals extent of Egypt's security challenge