There was no sign of life from under the rubble, and Atlantic City Deputy Fire Chief James Foley said the operation had changed from rescue to recovery.
Eighteen workers remained hospitalized last night, six in critical condition.
The collapse occurred about 10:40 a.m. when the top five floors toppled onto one another at one end, sloping down at a steep angle, as workers poured concrete, State Police Capt. Ed O'Neill said.
The cause was not known last night, but Gary Roskoski, area director for the federal Occupational Safety and Health Administration, said the agency would look into reports that witnesses had heard cracking as early as a week ago and investigate whether the concrete pillars had dried before supports were removed.
"We'll be looking at the blueprints and looking exactly at what was built according to the blueprints," said Roskoski, whose agency will lead the investigation. "We're going to look into any and all information we get."
Last night, flashlights cut through the darkness inside the garage, where only hours earlier workers had scrambled to escape a flood of wet concrete.
"The guys who were pouring concrete just got swallowed up," said glazier Eric Rosenberg, who watched from an adjacent tower. "The floors kept dropping. We saw some of the guys crawling away into a flat roof."
"I heard something that sounded like falling," said Bryson Shope Jr., a laborer who was on the seventh floor. "Ten seconds later, it started falling on us."
After running to one of the ramps, "we turned around to see if we could help. There was nothing left. All the floors were gone."
Shope made his way to a landing with about 10 other workers. "Guys were covered with concrete - you couldn't recognize them. One guy was yelling he couldn't feel his legs."
