Furious officials launched investigations of a blazing hot Florida nursing home where eight people were found dead Wednesday after Hurricane Irma left the building without air conditioning.

Democratic U.S. Sen. Bill Nelson called the disaster at the Rehabilitation Center at Hollywood Hills, in the town of Hollywood, about 20 miles north of Miami, "an emerging scandal of gargantuan proportions."

He said it was "inexcusable" that no one appeared to have called 911 as residents in their 70s, 80s and 90s sweltered without air conditioning in the summer Florida heat overnight.

A nursing home employee told NBC Miami that the building was cool on Tuesday but that he returned Wednesday morning to an overheated facility.

Florida Gov. Rick Scott called the situation "unfathomable," promising to "aggressively demand answers on how this tragic event took place."

Hollywood police launched a criminal investigation, and agents from the state attorney general's office and the state Agency for Health Care Administration were on the scene, authorities said. State officials closed the facility Wednesday night and barred it from admitting new patients.

"This was a terrible incident. The scene was chaotic when I arrived," said Dr. Randy Katz, medical director for emergency services at Memorial Healthcare System, where about a dozen of the 158 people who were evacuated from the facility were admitted for respiratory distress, dehydration and heat-related issues.

Katz said so many patients needed assistance that his hospital, which is just down the street, called in more than 50 doctors, nurses and other staffers under a mass casualty protocol.

"I've definitely seen mass casualties and things to that extent, but this is something unique, something extremely sad and unfortunate for these patients and their families," Katz said.

The Broward County medical examiner identified the victims as: Carolyn Eatherly, 78; Miguel Antonio Franco, 92; Estella Hendricks, 71; Betty Hibbard, 84; Manuel Mario Medieta, 96; Gail Nova, 71; Bobby Owens, 84; and Albertina Vega, 99.

No official cause of death was given, but authorities described the deaths as heat-related.

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