The ATF's Robert Elder is leading the arson investigation.
"Following an extensive scene investigation we have determined that this fire is an incendiary fire, meaning that the fire was intentionally set. So in layman's terms, we know we have an arson fire."
The store's 60,000 square foot warehouse on the North Freeway burned to the ground last Thursday night. Investigators estimate losses at between $15-20 million. Elder says story owner Jim McIngvale has been interviews by investigators.
"Mr. McIngvale has been very cooperative. He has given us everything we've asked for. We certainly feel for his loss. He just wants the person responsible caught."
In a written statement, McIngvale says he's thankful for the support shown by the community. He says he wants anyone with information on the fire to call investigators or Crime Stoppers at 713-222-TIPS.Î¾