About 30 percent of the three-story structure collapsed around 3 a.m. Monday, Lake County Fire Rescue Battalion Chief Tony Cuellar said. The villa at the Summer Bay Resort had already been evacuated and no injuries were reported. Cuellar said authorities were also concerned about another section of the villa, which was sinking.
The sinkhole comes five months after one elsewhere in Florida killed a man.
Monday's 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.
The villa houses 24 units and about 20 people were staying in it at the time, Cuellar said.
Authorities were called to the scene, about 10 miles west of Disney World, late Sunday where they found that the building was making popping sounds and windows were breaking.
A nearby villa was also evacuated as a precaution, Cuellar said.
Cuellar said there was a gas leak but the gas has since been shut off.
Witnesses told The Associated Press they could hear a cracking sound as the villa began sinking. A large crack was visible at the building's base.
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 the outage 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, of Berona, N.J.
In an interview aired on ABC's "Good Morning America," Maggie Ghamry, a guest at the resort, said that when she first heard shaking and glass breaking, she thought it might be kids running down the hall.
"Next thing I know, people are yelling 'get out of the building, get out of the building,'" she said.
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.