The cause of the fire that swept through a former Kmart in Minneapolis might never be known.

Minneapolis officials announced Tuesday that an investigation into the blaze, which broke out Friday in the Lake Street building, is complete, and "the final origin and cause of the fire are undetermined."

Investigators also announced there don't appear to have been any casualties in the fire. There were no initial reports of injuries, but to be sure, cadaver-sniffing dogs and infrared cameras were used to explore and analyze the building, which had already been slated for demolition. "No victims were detected," a statement from the city reads.

The fire has accelerated the city's plans to demolish the building and redesign the area, but the project had been delayed — the latest chapter in challenges the city and neighborhood have faced dating back to the store's opening in 1978.

On Tuesday, the city's statement said because the fire investigation is complete, demolition plans can now proceed, but no details were offered.

"These plans will become clearer in the coming days, including the start date of that work," the statement reads.

On Tuesday afternoon, the parking lot was fenced off up to the sidewalk on Lake Street, First Avenue and most of Blaisdell Avenue. Burnt debris could be seen piled up behind concrete blocks.

University of Minnesota student reporter Hannah Ward contributed to this story.