Twenty people were killed and 23 injured when a massive rockslide hit a crowded Cairo shanty town on Saturday, sending rocks and boulders crashing down on dozens of houses, state news agency Mena said.

Tumbling rocks and earth destroyed many buildings in the Manshiyet Nasser shanty town in eastern Cairo, its close-packed houses and narrow alleys huddled at the foot of cliffs beside a highway, the sources said.

Dozens of police and rescue workers were sent to the scene, backed up by fire engines, ambulances and sniffer dogs, but locals were enraged at what they saw as an inadequate government response to the disaster.

Witnesses described hundreds of weeping, yelling residents and neighbours gathered around the cordoned-off site, cursing local authorities and saying they had relatives and friends trapped beneath the rubble.

'You've just got your hands in your pockets, you're not doing anything!' one man yelled at police standing nearby. 'If it were the shura council (the upper house of parliament), you'd have had the army in by now!' shouted another.

'It was horror. 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,' said Hassan Ibrahim Hassan, 80, whose house escaped the destruction.

One six-storey building was reduced to rubble by the landslide, witnesses said.

The shanty town of red brick houses and unpaved narrow alleys is famously overcrowded, with entire poor families sometimes crowded into a single room. Its buildings were all huddled at the base of cliffs next to a main Cairo highway.

A woman in a white veil was screaming, 'My children, my children! I didn't get anyone out, I need to see them, even if they're dead!'

Rescue efforts were moving slowly, and equipment for digging out survivors had not yet reached the site. Mena said authorities had requisitioned heavy lifting equipment.-Reuters