FRANKLIN PARK, Ill. (CBS) — The fire that destroyed a vacant motel in Franklin Park last week was deliberately set, investigators have ruled.

The three-alarm fire broke out shortly before 2 a.m. this past Thursday, in the vacant Super 8 Motel at 3010 Mannheim Rd. Flames were still shooting out of the building more than four hours later.

There were no reports of injuries, mainly due to the fact that the motel was vacant to begin with.

On Monday afternoon, Franklin Park fire officials borrowed an accelerant-sniffing dog from the state Fire Marshal’s office and took it to the site of the motel.

“The canine did indicate the presence of an ignitable liquid,” and the fire was deemed an arson, Franklin Park Fire Lt. Nick Steker said.

The ignitable liquid was found in the front lobby, where the fire was first spotted.

Steker gathered samples of the ignitable liquid and sent them to the Illinois State Police crime laboratory. He hopes to get the results in the next month or so.

Steker and a Franklin Park police detective will conduct interviews with people who saw the fire.

Pioneer Press contributed to this report, via the Sun-Times Media Wire.

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