CLERMONT (CBSMiami/AP) — A sinkhole has caused building housing vacationers at a Central Florida resort to collapse.

Lake County Fire Rescue officials said that about 50 percent of the three-story villa at the Summer Bay Resort, located about 10 miles west of Disney World, collapsed around 3 a.m. Monday. Guests were rushed out of their rooms just before one of the three-story buildings collapsed and another slowly sank.

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The building — which had housed 105 visitors — was stable by mid-afternoon, said Paul Caldwell, the development’s president. Two adjacent buildings, which each have 24 units, were evacuated as a precaution.

Caldwell said the resort underwent geological testing when it was built about 15 years ago, showing the ground to be stable, and that there were no signs before Sunday that a sinkhole was developing. He said all affected guests had been given other rooms and some guests — many of whom had to leave their wallets, purses and other belongings behind in the quick evacuation — had been given cash advances.

Resort workers were working to do “whatever we need to do to make it right,” Caldwell said.

Technicians were on the scene Monday afternoon to inspect the structures, determine when anyone might be able to go back inside, and decide whether belongs would be recovered.

Security guard Richard Shanley had just started his night shift late Sunday when he heard what he thought was screaming from the building. He said he thought some sort of violence might be going on.

“I come to find it was actually the building being pulled apart,” Shanley said.

He said the building seemed to sink by 10 to 20 inches and banisters began to fall off the building as he ran up and down three floors trying to wake guests. One couple with a baby on the third floor couldn’t get their door open and had to break a window to get out, he said.

“It’s a scary situation,” Shanley said.

Guests credited him with saving lives by knocking on doors as pieces of the building began to break off.

Witnesses said they could hear a cracking sound as the villa began sinking.

Luis Perez, who was staying at a villa near the sinking one, said he was in his room when the lights went off around 11:30 p.m. He said he was on his way to the front desk to report it when he saw firefighters and police outside.

“I started walking toward where they were at, and you could see the building leaning, and you could see a big crack at the base of the building,” said Perez, 54, who was visiting from New Jersey.

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Maggie Moreno, of San Antonio, was staying in a building next to the one that partially collapsed. She was woken up by firemen and police officers knocking on her door. She couldn’t get the door to her unit open all the way.

“It sounded like popcorn,” said Moreno, who was visiting with her husband, daughter and two grandchildren. “The building was just snapping.”

Caldwell, the development’s president, said a window popped in one of the rooms about 10:30 p.m. Sunday. A woman ran outside and flagged down a guard Shanley, who notified management. Another window then popped and a decision was made to immediately evacuate the building, Caldwell said. The process took 10 to 15 minutes, he said.

The section of the building sank into the ground over next five hours, said Amy Jedele, a resort guest who was staying with her fiancée, Darren Gade, in a building about 100 yards away. Residents who had been inside the building described hearing what sounded like thunder and then the sound of water, as if it were a thunderstorm, she said.

The first portions to sink were the walkways and the elevator shaft, Gade said.

“You could see the ground falling away from the building where the building started leaning,” Gade said. “People were in shock to see a structure of that size just sink into the ground slowly. … You could see the stress fractures up the side of the structure getting wider.”

Caldwell said the partially collapsed building, with 24 three-story units, is a total loss, and he was waiting on further inspections to determine any damage to the second and third buildings. The resort has about 900 units spread over a large area about 10 miles west of Walt Disney World.

“No one is hurt,” Caldwell said. “Thank God for that.”

The sinkhole, which is in the middle of the villa, is about 40 to 50 feet in diameter, Cuellar said. He said authorities think it was getting deeper but couldn’t tell early Monday if it was growing outward. A nearby villa was also evacuated as a precaution and that there had been a sign of a gas leak, but the gas had been shut off.

Summer Bay is described on its website as a luxury resort with condominiums, two-bedroom villas and vacation houses in addition to standard rooms. The site touts a clubhouse, atrium and poolside bar, and says the resort is on a secluded 64-acre lake.

Florida has a long, ongoing problem with sinkholes, which cause millions of dollars in damage in the state annually. On March 1, a sinkhole underneath a house in Seffner, about 60 miles southwest of the Summer Bay Resort, swallowed a man who was in his bed. His body was never recovered.

But such fatalities and injuries are rare, and most sinkholes are small. Sinkholes can develop quickly or slowly over time.

They are caused by Florida’s geology — the state sits on limestone, a porous rock that easily dissolves in water, with a layer of clay on top. The clay is thicker in some locations making them even more prone to sinkholes.

Other states sit atop limestone in a similar way, but Florida has additional factors like extreme weather, development, aquifer pumping and construction.

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