WINONA, MN -

Investigators are focusing an electrical cause of the historic fire that consumed several buildings in downtown Winona.

Deputy Police Chief Tom Williams said Tuesday the most significant burn and char marks are near an electrical conduit in the building where the fire apparently started — the Islamic Center of Winona.

He says federal, state and local investigators plan to dig through the rubble at the former Islamic Center again next week. A similar effort was done last Saturday by about ten investigators. Williams says heavy equipment, such as a crane, is too costly, that's why investigators are digging by hand.

The fire last Friday destroyed three buildings, including the Islamic Center, and heavily damaged a third.

Winona Fire Chief Curt Bittle sys all of the agencies involved in the investigation will meet on Wednesday, September 25 to do a scene reconstruction to help determine the cause. That was the first available date for all of the agencies to meet.

An official cause of the fire and final determination will not be released until some time after that meeting, Chief Bittle said.

They are not looking at anything suspicious at this point and there are no indications of the building having been illegally entered prior to the fire, according to Winona Fire Department Assistant Chief Jim Multhap.