Correction: An earlier version of this article stated that the first person to report the fire was an off-duty firefighter. It was an off-duty police officer who first reported the fire.

Two small dogs died in a house fire on Douglas Highway on Monday, Capital City Fire/Rescue Assistant Chief Ed Quinto said on scene.

An off-duty police officer noticed smoke at a little before 3 p.m. Tuesday and called it in, Quinto said. When officers arrived at the scene — a house at 4055 N. Douglas Highway — they saw smoke around the back of the house. Quinto said they went around to the back and found flames coming from a bedroom.

They knocked the flames down fairly quickly. When firefighters went into the home, they found that the owners weren’t home but two small dogs were.

“We tried doing CPR on them, giving them some oxygen and chest compressions,” Quinto said. “That didn’t work.”

The dogs died, Quinto said, and he did not specify what breed they were. The homeowners — a husband and wife — arrived and told responders that the dogs were their only pets. Quinto said no humans were harmed.

Fire Marshal Dan Jager released a statement Wednesday morning, saying the fire was unintentional and the most likely cause is that a battery pack was charging and caught fire. Damage to the house is estimated at $25,000, according to Jager’s statement, and the house was insured.

Traffic was stopped for more than half an hour on Douglas Highway, and a line that included two school buses stretched nearly back to the roundabout near the Douglas Bridge.

It was the second fire in 24 hours, as there was a minor fire on Riverside Drive on Monday night, according to CCFR’s Facebook page. The residents of the home had knocked it down by the time firefighters arrived, according to a later CCFR post. According to CCFR’s daily incident report, the cause of that fire was shorted electrical equipment.