INDIANAPOLIS -- Some new details are emerging in the aftermath of the deaths of five people and injuries to 45 more at the Indiana State Fair in the collapse of the main stage.

The Indiana Department of Labor is reviewing why the employer of one of the workers who died failed to notify the state of the fatal accident, 6News learned.

Watch: Uncut: Gov., ISP News Conference On Stage Collapse
View Slideshow: Indiana State Fair Concert Stage Collapses | What Happened? Kevin Gregory Explains State Fair Storm

Regulators are not releasing the company name until it can confirm why the company delayed reporting the death.

Under state law, a company has eight hours to report a job-related death to a hotline number that is running at all times.

6News has also learned that state law doesn't require building inspectors to inspect the type of stage rigging that collapsed.

Some of the inspectors working at the scene of the accident have expertise in construction and worked on overseeing the building of Lucas Oil Stadium.

Inspectors at the fairgrounds are legally responsible for checking that exits are not blocked, that there are enough fire extinguishers and that amusement rides are safe.

The rides on the Midway will be inspected on Monday.

Tammy Vandam, 42, of Wanatah; Glenn Goodrich, 49, of Indianapolis; Alina Bigjohny, 23, of Fort Wayne; Christina Santiago, 29, of Chicago; and Nathan Byrd, 51, of Indianapolis, were all killed in the collapse.

Several of the people who were injured remain in critical condition.

The collapse happened about 8:50 p.m. Saturday as Sugarland, a country music act, was preparing to perform on the fair's main stage.

The National Weather Service said winds estimated at 60 to 70 mph buffeted the stage ahead of a line of severe thunderstorms. A severe thunderstorm warning had been issued for Marion County before the collapse.

"There is an evacuation plan that is prepared. There were preparations in progress in anticipation of a severe storm arriving around 9:15," said Indiana State Police 1st Sgt. Dave Bursten. "Personnel were being put in place for an evacuation, if that were deemed necessary."

Indiana State Fair Executive Director Cindy Hoye said Sunday that the Indiana Occupational Safety and Health Administration is investigating the contractor responsible for temporary structure, Greenfield-based Mid-America Sound Corp., and that a company engineer from Tennessee was coming to the collapse scene.

"Mid-America has been a vendor for at least 10, 15 years here. They have done an extraordinary job of providing help with production of our free stages and also our grandstand," said Hoye, who was backstage at the time of the collapse. "I have a great deal of confidence in them."

Mid-America owner Kerry Darrenkamp released a statement Sunday afternoon.

“This is a devastating tragedy and we want to express our sympathy to the families of those who were killed or injured last night at the State Fair," the statement read. "We have already started an independent internal investigation to understand, to the best of our ability, what happened.“

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