A fire overnight in Lynnwood was contained to the shed where investigators believe it started, saving the house nearby and its residents. According to Snohomish County Fire District 1, the fire started in a workshop around 1 a.m. Monday at 6631 182nd St. SW in Lynnwood. Fire crews say magnesium may have been stored in the building, making the fire difficult to extinguish and causing it to threaten the house immediately next to it. The fire department said the siding of the house was only slightly damaged. No injuries were reported. The exact cause has not been determined.