Updated 06/11/14 – 8:35 a.m.

MOKENA, Ill. (CBS) — An elderly couple was killed in a house fire overnight in southwest suburban Mokena.

Firefighters pulled the victims out of a home near Catalpa Road and Magnolia Avenue, but it was too late.

Crews were called to the home around 3:20 a.m. Neighbor George Spear said he was awakened by the crackling and popping sounds coming from the burning home.

“I thought it was just fireworks; kids in the neighborhood messing around. Then I looked outside, and I could see the fire raging out of their window, so I called 911,” he said.

More than 40 firefighters from eight departments responded to the scene, and when they arrived, the house was already fully engulfed in flames, and a neighbor and a Mokena police officer were outside.

The officer had tried to get inside to help the residents of the home, but was beaten back by heavy flames and smoke.

“We tried getting in through the back, but couldn’t. It was too thick,” the officer told firefighters.

Firefighters were able to get inside, and located an elderly man and woman in the house.

“Crews were told that there was possibly victims trapped. Without the protection of a hose line, they went in, attempted a quick rescue. They found one victim in the hallway, removed that victim, went back in, and found a second victim in the back bedroom,” Frankfort Fire Protection District Assistant Chief Bob Wilson said.

Firefighters and paramedics attempted to save the two victims, but they had already been overcome by all the flames and smoke, and there was nothing emergency workers could do.

“They were put into ambulances right away, and the ambulance crews did whatever they could,” Frankfort Fire Protection District Chief Jim Grady said.

Once crews arrived, it was easy for firefighters to douse the flames, but it already had been burning for quite some time before Spear called 911.

“For the popping noise to wake me up out of a dead sleep, I mean it sounded like it had been going for a while. It was raging out the one window,” Spear said. “It’s terrible. What are they going to do? It’s a fire. Old people, didn’t get out in time, it’s sad.”

Spear said he knew the couple for 15 years; they were quiet and kept to themselves.

“She would walk around this neighborhood constantly. He was ill. He couldn’t breathe very well. He had emphysema and stuff like that, so he was on oxygen. So he just basically hung around the house,” Spear said. “He still cut the grass and stuff with his oxygen machine.”

The cause of the fire was under investigation, but firefighters did not believe it was suspicious. One fire official said the fire apparently started in a bedroom of the one-story frame house.

The couple’s names have not yet been released.

The police officer who tried to get into the home was treated for smoke inhalation at Silver Cross Hospital in New Lenox, then sent home.

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