(CNN) For three days, the staff at The Rehabilitation Center at Hollywood Hills scrambled to keep residents hydrated and cool after a tree fell onto a transformer that powered the air conditioning system.

By Wednesday, eight of the nursing home's residents had died. The causes of the deaths are under investigation to see if any of them were heat-related, said Raelin Storey, director of public affairs for the City of Hollywood.

"The initial investigation has determined that the facility's air conditioning system was not fully functional," the city of Hollywood, Florida, said in a statement. "Portable A/C units were being used in the facility, but the facility was excessively hot."

The nursing home said it was prepped for Hurricane Irma. The power generator was working, and the staff stocked up on seven days' worth of food and water. But they didn't anticipate they would still have to fight the intense heat with fans and portable air conditioner units.

"The Rehabilitation Center at Hollywood Hills expresses its deepest sympathy to the family members of the residents who passed away following a prolonged outage of our air conditioning system due to Hurricane Irma," the nursing home said in a statement.

"We are devastated by these losses. We are fully cooperating with all authorities and regulators to assess what went wrong and to ensure our other residents are cared for."

Florida Gov. Rick Scott ordered an emergency moratorium on Wednesday to prevent the facility from admitting new patients.

Three agencies have launched investigations into how this happened, but many questions remain unanswered. A criminal investigation is also underway, and a search warrant has been signed for the Hollywood Police Department, according to city officials.

"I am going to aggressively demand answers on how this tragic event took place," Scott said in a statement. "If they find that this facility was not meeting the state's high standards of care, they will be held accountable to the fullest extent of the law."

What happened -- and when

Families are struggling to understand what happened to their loved ones who died, who ranged in ages from 71 to 99. But here's what we do know, according to Hollywood city officials:

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Tuesday morning: The nursing home told the Broward County Emergency Operations Center that it had lost power, according to a statement by the center. A "mission-critical" request to restore power was made to Florida Power & Light. The nursing home was asked if it had any medical needs or emergencies, Broward County Mayor Barbara Sharief said in the center's statement. No assistance was requested.

That day, one patient was found dead and taken to a funeral home. The patient had a do-not-resuscitate order, according to Hollywood city spokeswoman Raelin Storey. No one called authorities to alert them, Storey said.

3 a.m. Wednesday: Someone called 911 for a patient suffering cardiac arrest. That patient was taken to Memorial Regional Hospital.

4 a.m. Wednesday: A second 911 call came in to transport another resident with breathing problems.

After the second call was completed, a fire lieutenant notified a battalion chief and called the Department of Children and Families to report concerns about the facility.

Shortly thereafter: A third 911 call came in for yet another patient transport -- this time prompting the fire department to send more crews to the nursing home to investigate.

In addition to the resident taken to a funeral home on Tuesday, three others were found dead on the second floor of the nursing home, and several others were in distress.

Around 5 or 5:30, Judy Frum, chief nursing officer at Memorial Regional Hospital, noticed that patients were coming to the emergency room with "extraordinarily high temps."

Since the hospital was a stone's throw away from the nursing home, Frum decided to walk over and investigate.

What she saw -- the patients in distress, the unbearable heat -- prompted her to trigger the hospital's mass-casualty alert.

"The temperature in that room would've definitely been a concern for anybody, not just the elderly," Frum told CNN's Elizabeth Cohen.

9:15 a.m. Wednesday: In all, 141 patients had been evacuated from the nursing home and were being evaluated by paramedics and hospital staff. Another four patients were evacuated from an adjacent behavioral health facility.

Paramedics rushed to evacuate the sweltering facility, but four more nursing home patients died in hospitals.

'I can't breathe. I can't breathe.'

Jeffrey Nova had been calling the nursing home where his mom lived, but he couldn't get anyone to answer the phone since Sunday.

Still, that didn't strike him as unusual, he said -- communicating with the staff had always been like "pulling teeth."

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Finally on Wednesday, he learned that his mother, Gail Nova, 71, was one of eight residents who died at the facility.

"I'm not quite clear on how this happened," Jeffrey Nova said.

He said he learned of his mother's death not from the facility, but from a reporter who got his name and contact info from a nursing home employee.

Betty Hibbard, 84, another one of the victims, was alive but extremely uncomfortable on Tuesday when her friend Jean Johnson came to visit.

"We went by to see her the day before she passed away," Johnson told CNN's Chris Cuomo. It was "terribly hot," she added, but at least the elevator was working.

"I've been there sometimes when it didn't," she said.

Without air conditioning, residents were kept in hallways near the cooling units as the days passed.

"She was sitting in front of a blower, and she almost cried," Johnson said of Hibbard. "She says, 'Jean, I can't breathe. I can't breathe.' I said, 'Honey, please don't talk.' "

The nursing home didn't have any ice to give her, and Johnson said she felt ignored by the staff.

In the early hours of Wednesday morning, Johnson went to visit her friend in the hospital. Hibbard was unresponsive.

"She hadn't really died, but she was gone," said Johnson, who later got the call that her friend had passed away.

In a statement, nursing home administrator Jorge Carballo said, "We are devastated by these losses."

"We are fully cooperating with all authorities and regulators to assess what went wrong and to ensure our other residents are cared for," Carballo said.

With a moratorium in place and an ongoing criminal investigation, the residents of Hollywood Hills will find new homes at other facilities, said Storey.

"That is a difficult proposition," she said. "There are not as many beds and facilities available as there are people with needs."

Dozens have already been released to other facilities and their families, but many remain in the hospital, according to Zeff Ross, CEO of Memorial Regional Hospital.

Vendetta Craig was told that her mother, 87-year-old Edna Jefferson, was in the best of hands at Hollywood Hills. Before the hurricane, the nursing home reassured her it was well prepared.

But Wednesday morning, a friend called her and said, "I don't want to alarm you, but I think you need to turn on CNN," Craig recalled at a press conference.

Her mother was among the survivors. Craig said that the staff at Memorial Regional Hospital was able to bring her mother's temperature down from 102.

"She opened her eyes. She looked at my eyes," Craig said. "Oh my gosh, that was the best thing."

But the experience left her upset about how the nursing home treated its residents.

"We throw away our elderly," she said. "That's my mother."

Questions arise

Authorities are now questioning how the conditions at the nursing home lasted for so long.

The Rehabilitation Center in Hollywood Florida on Wednesday

Carballo said the center immediately contacted Florida Power & Light and continued to follow up with them for status updates on when repairs would be made. City and state officials said they were in contact with the nursing home over the past three days and advised them to call 911 if they believed that the health or safety of patients was at risk.

"When asked if they had any medical needs or emergencies, (the nursing home) did not request assistance or indicate any medical emergency existed," Sharief said in a statement

Richard Beltran, a spokesman for Florida Power & Light, said in a statement: "What we know now is that a portion of the facility did, in fact, have power, that there was a hospital across the parking lot from this facility and that the nursing home was required to have a permanently installed operational generator."

The nursing home has a history of safety violations and citations, including two for not following generator regulations in 2014 and 2016 . In both instances , the nursing home corrected these deficiencies.

As power outages persist in Florida, the Hollywood facility is not the only one that has been affected by the storm.

The Florida Health Care Association , which represents 81% of Florida's nursing centers -- but not the Rehabilitation Center at Hollywood Hills -- said on Wednesday that about 150 facilities out of nearly 700 nursing home facilities in the state do not have full power services restored.

On Thursday, that number had fallen to 64.

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Federal law currently requires that nursing homes be kept between 71 and 81 degrees and have a backup power source in case of emergency. That backup power must be able to keep temperatures in a safe range for nursing home residents and whatever provisions are stored there, according to more recent regulations that must be implemented by November 2017.

The Florida Health Care Association has said it is working with the state to identify homes without power in greatest need so utility companies can prioritize them.

"This is an isolated incident and is not representative of the larger long term care profession in Florida," the association said in a statement.

Evacuations at another nursing home

The deaths prompted checks of other nursing homes in the area.

Police checked 42 nursing homes and assisted living facilities in Hollywood on Wednesday. Hours later, 79 residents from the Krystal Bay Nursing and Rehabilitation Center in North Miami Beach were evacuated to another facility because of the heat.

These South Florida facilities are among hundreds of nursing centers in the state. The Florida Agency for Health Care Administration , which licenses and regulates such facilities, says there are 683 nursing homes in the state with more than 84,000 beds.

In addition, there are more than 3,100 assisted living facilities with more than 99,000 beds.