CAIRO, Egypt (AP) _ A sandstorm that turned the sky from gray to red to eerie white enveloped much of Egypt on Friday, reducing visibility to zero in many places.

Cairo International Airport was closed and flights were diverted from the capital to the Red Sea coastal town of Hurghada or Aswan in the south.

Heavy winds blew down advertising billboards at the airport, injuring several airport workers and people en route to the terminals, airport officials said. One man was hospitalized.

Eight people were injured in the town of Beni Suef, 60 miles south of Cairo, when two minibuses crashed, sending one of the buses tumbling into the Nile. At least 10 elderly people were rushed to Cairo's Ein Shams hospital suffering from breathing problems.

The storm packed winds of 60 mph and was expected to engulf nearly all of Egypt, said Sherif Hamad, head of the Egyptian Meteorological Service.

Sandstorms are not unusual at this time of year, but ``we've never experienced such a powerful one,'' Hamad said. He predicted the weather would clear Saturday.

The storm came in from the Libyan desert at about midafternoon and was moving northeast, the meteorological service said.

As it moved, the sky turned from clear blue to gray, then to glowing red, then to an eerie white because of the mass of sand suspended in the air.

Excursion boats on the Nile, heavy with afternoon picnickers on the Muslim sabbath, pulled to shore as the winds whipped up the river.

Egyptian television interrupted its programming to warn people to take cover. Pedestrians fled into doorways and other shelters, cars stopped and shopkeepers tried in vain to shutter their windows.