"There are no red flags," he said.
All of the affected businesses experienced smoke and water damage, he said. The plaza's facade took the brunt of the flames, forcing demolition crews to strip it off Tuesday for safety.
Sean Jones, fire rescue chief at Natrona Heights Citizens Hose Company, said it took crews more than three hours Monday night to control the flames, which officials believe started between J&S Pizza and a vacant business where a sleep clinic was about to open.
He said investigators estimated the damage at $10 million Tuesday. Up to 15 businesses were affected.
Three firefighters were treated for medical issues resulting from the stress of the fire, Chief Jones said. Two for chest pain were admitted to the hospital and one complaining of nausea was released.
The fire rekindled at the State Farm insurance building before 10 a.m. Tuesday, but crews were able to contain it in minutes, Chief Jones said. Firefighters also poured water atop the Dollar Bank, where people reported seeing smoke that morning.
Thirty fire companies responded.
"Besides the loss of tax revenue, it's going to affect a lot of families," said Harrison commission President George Conroy.
Chief Jones estimated at least 100 people would be out of work, including 35 to 40 J&S Pizza employees.
"This is the anchor store of this whole plaza," said owner Debora Malvone.
A Christmas tree stood intact inside the restaurant -- but unlit, as the affected stores remained without power.
Mr. Brucker said the direction of the wind Monday night blew the flames in such a way they more heavily damaged the facade of the shops near the end of the plaza.
Extra security on was duty Tuesday while crews were working, Chief Jones said. All the businesses are insured, he added, but Mr. Brucker said it will take time to contact each insurer.
Heights Plaza was built in the 1950s, and residents remember the mall as a location once popular for retail shopping and community activities around the holidays.
Written by Pittsburgh Post-Gazette