Rescuers continued to search for survivors Monday after deadly tornadoes tore through Kentucky and neighboring states over the weekend, decimating entire towns and leaving dozens dead.

Kentucky Gov. Andy Beshear said in a Monday afternoon update that 74 people in the state have been confirmed dead and over 100 people were unaccounted for, with both numbers expected to grow.

The governor estimated Monday morning that it would take “a week or even more before we have a final count on the number of lost lives,” saying the “mountain of waste” left behind by the twisters included perished livestock.

Flags at government buildings will be flown at half staff for a week beginning Tuesday, and a state fund will pay for the funerals of those who have died, Beshear said.

The series of unseasonal storms ripped through several states across the Midwest and South overnight on Friday, leveling a candle factory and entire communities in Kentucky while also hitting a nursing home in Arkansas and an Amazon distribution center in Illinois.

Climate change likely made the tornado outbreak worse by altering or amplifying the ingredients — like higher-than-average December temperatures — that produced the tornado outbreak, meteorologists have said.

On Sunday, President Joe Biden approved a major disaster declaration for Kentucky, providing federal aid to those in at least eight counties after the storm destroyed homes and left thousands without power.

Beshear said he was “grateful” for the declaration, which was the fastest he had ever seen, and that Biden had called him three times Saturday. The president plans to travel to the state Wednesday for a storm briefing and to survey damage in Mayfield and Dawson Springs.

More than 300 National Guardsmen were on the ground in Kentucky Monday, while 30,000 homes remained without power.

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Dozens of families were mourning, with the Kentucky governor among them as he confirmed that he too had lost loved ones in the storm.

Many others were still waiting to hear whether family members had survived, with spotty cellphone service in affected areas making it even more difficult to determine who was still missing.

“I’m really sorry,” Beshear said Sunday to those still searching for answers. “You’re not supposed to lose people like this, and to not know and not have the information has got to make it that much harder.”

“This is the deadliest tornado event we have ever had,” Beshear said Sunday.

At least eight people were confirmed dead after the roof of a candle factory in Mayfield collapsed, with survivors describing harrowing scenes.

Mayfield Mayor Kathy Stewart O’Nan told NBC’s “Nightly News” that the town “is gone.”

“We knew it was bad, but not till the sun started coming up did we look at it and saw matchsticks,” she said. “Our hearts are broken.”

Only one Mayfield pharmacy was operational, with another expected to open Monday. Beshear advised people to bring their medication bottles, though noting grimly “the pharmacy recognizes that you probably don’t have them.”

And Mayfield was not the only town left destroyed by the disaster, with Beshear telling CNN’s “State of the Union” on Sunday: “I’ve got towns that are gone,” including half of his father’s hometown, Dawson Springs.

In Graves County, a 3-year-old child was also confirmed to be among Kentucky’s dead, with two other counties losing at least a dozen community members to the storm.

While Kentucky was the hardest hit state, the devastation tore beyond its borders, with several people killed in Illinois, Tennessee and Arkansas.

In Illinois, at least six people were confirmed dead after an Amazon warehouse in Edwardsville was decimated.

Amazon founder and Executive Chairman Jeff Bezos said in a tweet on Saturday that he and others were “heartbroken over the loss of our teammates there.”

The Occupational Safety and Health Administration is investigating the collapse, according to the agency. Amazon spokespeople said Monday that the probe is welcome, adding that the structure was built according to code.

Illinois Gov. J. B. Pritzker on Monday issued a disaster proclamation for the counties impacted by the storms and tornadoes.

In Tennessee there were at least four confirmed deaths, with two killed in Missouri including a young child. In Arkansas, at least two people were confirmed dead, including one person at a nursing home in Monette.

Homeland Security Secretary Alejandro Mayorkas said in an interview on MSNBC’s “Morning Joe” that he and his team visited western Kentucky on Sunday.

Describing the devastation, he said: “The pictures don’t do the travesty justice. There’s nothing like seeing it up close and personal.”

“It was nothing but rubble,” he continued. “We saw, there, a backpack recovered, an individual’s shoe, a cellphone that had 27 missed calls recorded on it.”

He said survivors are being provided with water, food, clothing and blankets and will be reimbursed for temporary housing.

Vice President Kamala Harris, during unrelated remarks Monday, said: “Our hearts, of course, go out to the communities that have been impacted. You’ve lost so much and so quickly. We are committed — the president and I, and our administration — to helping you and helping to heal the wounds, which will probably be long lasting.”

Michael Dossett, director of the Kentucky Division of Emergency Management, has said efforts are already underway to start rebuilding following the weekend’s disaster.

Speaking Sunday at a news conference, he said officials were in the process of drafting “a plan to move forward, bringing new housing construction.”

However, he said he also wanted to manage expectations, warning “this doesn’t happen overnight.”

In Mayfield, residents told NBC News that they were ready to rebuild as they grappled with the devastating loss of their homes and businesses.

“There’s nothing left here. So, all we can do is just clean up and start again,” Wayne Flint, whose family restaurant was flattened in the disaster, said. “That’s what we’re going to do. … I don’t know what else to do.”

“It’s going to get better. … Neighbors help neighbors. We’re going to be back,” another resident said.

Beshear said he suspected that “thousands” of homes had been lost.

Some state parks were open for housing, he said, calling on volunteers to help out. “We’re not going to let any of our folks go homeless,” he added.

The governor said that in his rush to write notes on the number of dead and missing Monday morning, he had grabbed one of his kid’s school notes on inertia with the reminder, “An object in motion will stay in motion.”

“We will keep putting one foot in front of another and push through this,” Beshear said. “We’re not going anywhere, we’re going to be with you today, we’re going to be with you tomorrow and we’re going to be with you to rebuild.”

Speaking later on Monday afternoon, Beshear advised Kentuckians to be careful and avoid downed power lines as people begin to sort through the wreckage of their battered towns.

“As you begin cleaning up, take photos. Make a list of your damaged property. This is going to be really important for claiming public assistance. You need to document everything you possibly can,” Beshear said.