COEUR d'ALENE - A fire destroyed a duplex under construction in Coeur d'Alene on Sunday night and damaged three neighboring single-family homes.

Witnesses reported seeing two individuals leaving the structure at 1611 Nettleton Gulch Road earlier, said Coeur d'Alene Police Sgt. Brett Walton. A description of the two was not obtained.

"Just that two individuals were seen leaving, and the fire started a short time after that," Walton said.

Detectives were arriving on the scene to work with fire investigators, Walton said.

No injuries of residents were reported. A firefighter sustained a minor injury with a sprained ankle.

The fire was reported around 8 p.m.

Glenn Lauper, Coeur d'Alene Fire deputy chief, said the fire started upstairs in one of the duplex units, then spread to the other duplex.

"The fire damaged the vinyl siding of three neighboring homes that were 20, 40 and 60 feet way, so it was a pretty hot fire," Lauper said. "The vinyl just ignited and melted."

The total damage to all the structures was $200,000.

Lauper said the shell of the duplex under construction was up and it was in the process of having insulation and Sheetrock installed.

Lauper said he couldn't comment on the possible cause or whether the fire was suspicious.

"The fire is under investigation and we'll likely release further information (today)," he said. "We have a lot of witnesses and we're contacting more. The duplex didn't have electricity, so we were able to rule that out (as a possible cause)."

Lauper declined to release the duplex owner's name and said he didn't immediately know who the contractor is. He also declined to comment on the contents inside the duplex, including construction equipment and materials.

"The owner is upset and cooperative with what we're trying to get done," he said.

Neighbor Jackie Wagner was enjoying a relaxing evening watching TV, she said, when she heard a fierce knocking.

"It was like, boom, boom, boom," Wagner said.

She opened the door to see a frazzled stranger and a line of cars stopping out front.

"This guy, and I didn't know this person, and there's this line of cars, and he's all, 'Get out of your house, there's a fire next door,'" she said.

Neighbors said the fire was put out in roughly 15 minutes. A massive column of smoke had billowed above the neighborhood.

The structure was left blackened and skeletal, and the exterior of one side of Wagner's home melted off.

Wagner said she had freaked out when she saw flames a few feet high emerging from the structure several feet away from her own home.

"It went up so fast," she said. "Your whole life flashes before your eyes."

Her boyfriend James Whittle said that they hastened out with the pets and Wagner's two children, ages 14 and 15.

Wagner said the interior of her home seemed to be fine. She was renting, she said, and didn't think she had to pay for damages.

"I just talked with my landlord, who said not to stress about it," said Wagner, whose home is on Hat Trick Lane, running perpendicular off of Nettleton Gulch Road.

Neighbor Joe Deats said he picked up a hose to try to deter the flames as Wagner and her family fled their home.

"It was burning so fast and hot, I was spraying myself, and spraying the house, then spraying myself," he said. "Finally, I thought, 'This is a losing battle.' You had to back up and watch it burn."

Kootenai County Fire and Rescue and Northern Lakes Fire assisted Coeur d'Alene Fire.