DES MOINES, Iowa (AP) — Federal experts have wrapped up their investigation of a downtown Des Moines fire without determining the cause. Investigators with the Bureau of Alcohol, Tobacco, Firearms and Explosives said Sunday there is no sign the March 29 fire in the former Younkers building was set intentionally. But it’s not yet clear what caused the fire at the building built in 1899 that was being renovated into apartments at the time.

Control of the devastated building will be turned over to the developer. City officials will now work to determine what development might be done on the block after the fire.