Cairo's international airport closed its airspace on Monday between 11:00 and 12:30 CLT (09:00 - 10:30 GMT) because of military exercises, airport sources told Al-Ahram Arabic news website.
The sources said the operators at Cairo airport coordinated to schedule takeoffs and landings to avoid congestion in departure halls, while arranging for some flights to land at alternative airports while the airspace was closed.
Military exercises are common in Egypt, and the airspace above Cairo has been closed on several occasions before. On Wednesday, Cairo's airspace was closed for the same reason.
Airports nationwide are expecting the arrival of tens of thousands of Egyptian pilgrims, with the hajj season having ended on Saturday.