Investigators on Monday began searching for the cause of a fire Sunday that destroyed one Pekin home, heavily damaged another and killed seven pet cats.

Eight people fled from the structures without injury when the fire broke out at about noon at a two-story house 346 Caroline St. and quickly spread to another at 342 Caroline.

“There was a lot of fire in a very short time,” said Pekin Fire Department Chief Kurt Nelson.

Flames engulfed the first house after they ignited its aged petroleum-based tile siding, he said. The material “gives off a ton of heat” when it burns. Strong winds also helped spread the flames to the second home.

Nelson said fire department and insurance company investigators will seek to learn whether faulty electrical wiring in the first house caused the blaze. A resident there told firefighters the structure had electrical issues.

Four cats perished in the first house and three died in the second, while four dogs were safely evacuated from it.

Firefighters required 1 1/2 hours to bring the blaze under control and remained on the scene for four hours. A fire department captain noted that the first home had no firestops containing fire-resistant materials between its floors, allowing flames to spread upward and remain burning within its walls.

Nelson said the first home will be razed, while the second might be repairable. He estimated total damage not including the homes’ contents at about $150,000.