Dozens of houses in the impoverished Duwayqa district were hit by boulders and rocks about 9 a.m. It was not clear what caused the rockfall, which resulted in boulders up to 70 tons falling on the homes, the BBC reported Saturday.

"It was horror," said Hassan Ibrahim Hassan, 80, whose home survived the destruction. "The power went out, we heard a loud bang like an earthquake and I thought this house had collapsed. I went out, I saw the whole mountain had collapsed."

Witnesses said hundreds of distraught residents were scrambling to find relatives and friends -- some trapped under the rubble. While people began digging with their bare hands, rescue teams were forced to wait for cranes and heavy lifting equipment before moving the huge boulders.

Witnesses said some people quickly removed the bodies of their relatives from the accident scene, making it difficult for authorities to pinpoint the actual number of dead, reported the African Press Agency, which said there were at least 30 fatalities and 35 people injured.

IslamOnline.net reported 31 dead and 23 injured.

Rescue teams were working into the night to find those trapped under the wreckage of the collapsed houses.

Salah Mahmoud, chairman of the National Research Institute of Astronomy and Geophysics in Cairo, warned there could be further slides, the press agency said. He recommended evacuating residents from the area.