BOISE -- Investigators have determined that a fire that razed the International Market in Boise was arson.

The two-alarm fire started inside the business the night of Sept. 5. More than a dozen vendors, many of them refugees, sold food and other wares in shops inside the market building.

The entire building was gutted in the fire, forcing vendors out of business.

The blaze was determined to have started in a wastebasket in a kitchen inside the market. Investigators originally said the fire was an accident, but reversed that opinion Tuesday morning after uncovering new information.

"We interviewed a number of vendors in the building and worked with a variety of outside agencies, including private fire investigation experts, to come to this conclusion," Boise Police Fire Investigations Sergeant John Terry said in a press release.

Police say they have not found any evidence that the fire was set with the intention of physically harming anyone inside the building.

The owner of the Boise International Market, Lori Porreca, told KTVB over the phone that she's shocked by the news and heartbroken that someone would set the fire intentionally.

The investigation is ongoing, and police have asked for the public's help in determining who is responsible for the arson.

A reward of up to $5,000 is offered for any information that leads to the arrest or conviction of the culprit. Anyone with information should contact Idaho State Fire Marshal's Office Arson Line at 1-877-75-ARSON, or Crime Stoppers at 343-COPS.