Five people had minor injuries — and a cat was killed — during a five-alarm fire at a Hempstead apartment building Saturday afternoon, authorities said.

The blaze heavily damaged two or three apartments in the six-story, 36-unit building at 36 Cathedral Ave., said Michael Uttaro, Nassau County assistant chief fire marshal. Several other units appeared to have also been affected.

About 60 residents of the co-op were displaced by the fire, officials said.

It took 20 fire departments about two and a half hours to knock down the fire that was reported at 2:42 p.m., Uttaro said.

Four of those treated for injuries were firefighters, who battled the inferno while temperatures outside reached into the 90s. All had heat exhaustion or hyperthermia, officials said.

A male resident of the building was taken to a hospital and treated for similar injuries. He was able to rescue his two cats from the scorched building, authorities said.

advertisement | advertise on newsday

But Georgia Laudani, 35, who lives in the apartment where the fire began, said her own cat Trixie — a 5-year-old feline with three legs — didn’t survive.

“They’re going to try and get her body out for me,” said a tearful Laudani, who was out celebrating her fifth wedding anniversary when the fire broke out in her second-floor unit. Firefighters say the cause is under investigation, but that it’s not considered suspicious.

“It’s my wedding anniversary,” Laudani said. “My whole apartment’s in ashes.”

It was unclear late Saturday whether any other animals were hurt in the blaze.

Red Cross volunteers at the scene said they were helping dozens of displaced residents find places to stay.

The building’s occupants described a chaotic scene in the moments after the fire broke out, as people fled via fire escapes and stairwells. A postal service worker on the property could be heard yelling for people to “Get out, get out!” witnesses said, as tenants grabbed what valuables they could and ran.

“The flames were jumping out of the windows, bright orange like, like it was a movie,” said Sarah Kramer, who was staying in her sister’s apartment and smelled smoke as she watched the news. She used a fire escape to rush downstairs, where she watched the fire roar.

“The heat was so intense, the firefighters looked like they could barely breathe,” Kramer said. “They looked like they were ready to collapse, but they did the job.”

Laudani said she was glad to have escaped safely, but mourned the loss of her cat and all her valuables, including the ashes of family members.

“It’s overwhelming,” she said.