The cause of a weekend house fire on Jean Street is in the books as undetermined. City fire inspector Eric Nordlund says their investigation of the blaze has been hampered by conditions inside the vacant house. He says besides being damaged by the fire, the house is covered by a tremendous amount of ice inside and out. Nordlund says it appears someone may have been entering the house without the owners permission, but they can't say if anyone was inside prior to the blaze.