An explosion at a Columbia City warehouse last month was caused by an “unintentional natural gas leak ignited by an independent ignition source,” the Indiana State Fire Marshal's office said Tuesday.
Zachery Sparkman, 34, of LaOtto was found inside the warehouse after the May 22 explosion, Indiana State Police at Fort Wayne said. The cause and manner of his death are pending a final autopsy report from the Northeast Indiana Forensic Center in Fort Wayne, the Whitley County coroner's office said.
State police said they had not completed their part of the death investigation pending the report.
During the investigation, the Indiana state fire marshal's office examined and tested all the natural gas lines in the building. Minor leaks were found in several connections, likely from the explosion and fire, the fire marshal's office said.
A gas valve along the back wall, near Sparkman's location, was examined and showed the most significant leak in the building. Sparkman was known to smoke, the fire marshal's office said.
Investigators found no evidence of tampering with the building's natural gas system, the office said.