Rescue teams worked around the clock to locate survivors. In the afternoon there was a roar of applause as tearful rescue workers pulled out a middle- aged couple. Alberto Viola, who was conscious, had badly shattered legs but was out of danger. His wife, Luciana, underwent surgery for internal injuries and is in intensive care.
By late last night, hopes of finding more survivors in what was the modest block in the outer Rome suburb were fading. Emergency workers recovered 16 corpses including three children. One was just a few months old. Fifteen other people are unaccounted for.
Renzo Rinaldi, an eyewitness, said: "There was a dull boom. It was like a snowstorm, you couldn't see anything. When the huge cloud of dust cleared there was just a gaping hole where the building once stood. It was as thought the earth had opened and swallowed it up."
One of the first to arrive was a fireman, Maurizio Fumatelli, whose family lived there. He, and neighbours in their pyjamas, began digging with their bare hands. Even after the lifeless bodies of his parents and two brothers were brought out Mr Fumatelli continued to dig.
Others could only stare and sob as the orange bulldozers lifted off the concrete pillars and twisted metal. Firemen passed out buckets of debris and sniffer dogs nosed the rubble.
The causes of the collapse are unclear. Initially a strong smell of gas fuelled reports of an explosion. But the fire service commander, Luigi Abate, said the smell was a consequence, not a cause, of the collapse. "If it had been an explosion, neighbouring buildings would have been damaged but they are intact, including the windows," he said.
Franco Barberi, undersecretary of Civil Protection, said: "From the small quantity of debris, it seems the building simply folded in on itself."
Locals sought assurances that the cause was not geological subsidence that might put other homes at risk.
The building dated from the 1950s when housing in Rome went up cheap and fast. Restructuring work was underway in part of the block. "This is a district where they have built illegally without proper planning permission or respect for safety," said an indignant elderly local. "And no one checks what the effect of this is on the building."
Local and central government have promised swift action. On visiting the scene Rosa Russo Jervolino, the Italian Interior Minister, described it as "an enormous tragedy".
Francesco Rutelli, the Rome Mayor, said: "If we find that behind this tragedy there is negligence those responsible should be punished severely." He added that that referred to private or public entities.
The city council and Rome magistrates have begun inquiries. The Pope was among those to express his condolences during his weekly audience and the Basilica of St John the Lateran is being made available for the funerals of the victims.Reuse content