FOGGIA, Italy -- Searchers found bodies near the stairwell of a collapsed apartment building in southern Italy on Saturday, raising the death toll to 52 in the nation's worst building collapse in decades.

Ten people were still missing from Thursday's early morning disaster.The number of victims found in the area where the building's stairwell used to be "makes us think that those people were running downstairs to get out of the building, evidently warned by the shaking," said Luigi Panarese, a fire department official in Foggia, 70 miles northeast of Naples.

Survivors say the building shook for two or three minutes before it fell, giving some people time enough to run door to door to alert their neighbors. Sixteen people escaped or were rescued.

Italian officials attended a funeral Saturday for 11 of the victims.

The disaster was Italy's deadliest building collapse since 1959, when a falling apartment block crushed 58 people.

Authorities believe a structural failure caused Thursday's disaster but haven't yet determined the precise cause. A cave-in in the sandy soil beneath the 30-year-old building also has been suggested.

Dozens of residents of surrounding apartment buildings built at about the same time have fled, fearing the same fate. Foggia officials have received scores of complaints about cracks and other worrying signs in the city's buildings since the disaster.