CINCINNATI – A hospital spokesman says a worker who was injured when a floor collapsed at an Ohio casino construction site remains in serious condition a day later as investigators work to figure out what happened.

More than a dozen workers were hurt Friday morning at the Horseshoe Casino Cincinnati site, where they were pouring a section of concrete floor.

Most of the injured had been treated for bumps and scrapes and released by Saturday afternoon. One man was hospitalized in serious condition.

The Cincinnati Enquirer reports crews were stabilizing the site Saturday amid investigations by city and workplace safety officials.

The collapse occurred weeks after a similar accident at a Cleveland casino with the same developers. The developers have said there’s no link between the two accidents.