CAIRO, Egypt -

Massive boulders peeled away from a cliff and buried dozens of homes in an Egyptian shanty Saturday, killing at least 24 people, authorities said. Rescuers were digging by hand to reach any survivors.

At least eight boulders, some the size of small houses, fell from the towering Muqattam cliffs outside Cairo and buried about 50 homes in the massive Manshiyet Nasr slum, one of many densely populated shanties ringing the city of 18 million.

A security official said 35 people were injured and many more may be buried under the hundreds of tonnes of rock that fell. He spoke on condition of anonymity because he was not authorized to speak to the press.

"My whole family is underneath the rock," sobbed Anwar Ragab as he watched a body being pulled from under the rock. "I don't know what to do, I can't do anything -- I just want my children back."

The town was covered by a thick layer of dust and the scene was chaotic as men and women screamed in grief and blamed the government for a slow rescue operation. People tried to lift the massive rocks by hand, calling out the names of relatives and family members stuck under the debris.

Slums like Manshiyet Nasr at the base of the cliffs are built by migrants from the countryside looking for work in Cairo, which suffers from a severe housing shortage. The buildings are crudely built and lack basic services.

Resident Mohammed Hussein said contractors were working on shoring up the cliffs as they became increasingly unstable, but they could not complete their work until the government resettled the community below.

"The contractor who is stabilizing the mountain asked the government to resettle everyone at least 50 kilometres from the mountain because he didn't want the rocks he was removing to fall on the people," Hussein said. "The rocks are soaked with water and so are more brittle and prone to falling."

The rock slide and the slow response comes after a string of other disasters in the country led to accusations of government neglect and incompetence. Among them, a fire that gutted the upper house of parliament in August, a fire that destroyed another Cairo slum in 2007 and a ferry disaster that claimed 1,000 lives in 2006.

The government issued a statement saying survivors of the rock slide would be transferred to new housing for the night and given all necessary aid.

"We are following the case step by step and providing the care and comfort for the residents," Prime Minister Ahmed Nazif said in the statement. "We would like to remind people the danger of building informal housing in dangerous areas."

The boulders came crashing down at 7 a.m., when most residents were still sleeping after waking earlier to eat ahead of the daytime fast of Islam's holy month of Ramadan.

"I couldn't find my house this morning," said Mustafa Abdel-Fatah, who spent the night at a friend's house in a different neighbourhood. "I could only see rocks on top of everything."

Haidar Baghdadi, the parliamentarian for the region, told Al-Jazeera news channel that buried residents were calling for help from under the rubble using cellphones.

He added that the area was known to be dangerous and the residents were supposed to be resettled to government housing. He also criticized the lack of government emergency response.

"We should have removed these rocks five years ago to protect the people underneath or moved the people," he said, blaming the Housing Ministry for the disaster.