The bodies of a mother and her four children were found Thursday inside a central Arkansas duplex, and authorities were investigating whether they were killed by smoke inhalation from an overnight fire that was extinguished before firefighters arrived.

A maintenance worker found the bodies around 7 a.m., about an hour after firefighters first knocked on the door to follow up on a neighbor's report of smelling smoke. Nobody answered and thermal imaging didn't detect any sign of a fire from outside, so the firefighters left without entering, Jacksonville Fire Battalion Chief Bob Thornton said.

Firefighters had three engines deployed to a nearby house fire, and they believed it to be the source of the smoke smell, Thornton said. After firefighters returned to the scene following the discovery of the bodies, they acknowledged a fire might have burned overnight and "smoldered itself out," he said.

Thornton said authorities didn't suspect foul play but haven't confirmed the cause of death for Marilyn Beavers, 31; her son Dequan Sigleton, 11; and daughters Sydni Singleton, 9; Haylee Beavers, 7; and Emily Beavers, 4.

Phil Nix, the executive director of the Jacksonville Housing Authority, said the maintenance worker found the bodies in their bedrooms and saw extensive smoke damage in the kitchen.

"The damage around the stove and the cabinets beside the stove," Nix said. "Evidently, something was cooking and caught fire."

Jacksonville police spokeswoman April Kiser said there was smoke and soot damage throughout the duplex and in the ventilation system but no fire damage to the outside of the duplex. Authorities declined comment on where the fire started.

Friends said the family members had just been approved for a new house and were planning to move soon. Barbara Brooks said her friend had even asked for help packing.

"She was so excited," Brook said. "She said it was a new step in her life."

The oldest child was a football standout who often played in the field near the home, neighbor Kirk Green said.

"I got the call this morning and I couldn't believe it," said Green, who was godfather to the family. "The last thing I heard him say was he called me and said we were going to get together this weekend and we're going to the park."

Jaylen Washington, 16, said his 11-year-old friend also played basketball but was particularly passionate about football.

"I told him he couldn't play football, and then he proved me wrong," Washington said. "He was a good kid. He wanted to go to the NFL and everything."

Brooks said the mother would often take her children to the skate park or the circus.

"The kids were her world," Brooks said. "We used to take our kids everywhere together. All of her time was with her kids."

Jacksonville, a town of about 28,000 people, is about 20 miles northeast of Little Rock and home to the Little Rock Air Force Base, a training base for C-130 aircraft.

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