The blaze broke out in the 2½-story Cape Cod on Macopin Road, south of Bubbling Springs Park, just after 8:45 p.m., Police Detective Sgt. Eric Darnsteadt said.
The fire went to four alarms a little over an hour later and then a fifth 20 or so minutes after that.
All six West Milford fire companies and two units from West Milford First Aid Squad were joined by firefighters from Ringwood, Bloomingdale, Wanaque, Pompton Lakes, Kinnelon, and Highland Lakes, Darnsteadt said.
The fire was declared under control shortly after 11 p.m.
Township fire officials summoned the Passaic County Prosecutor's Arson Unit to investigate, a utility crew to deal with downed power lines and DPW workers to sand the icy roads.
A joint investigation by the West Milford fire marshall, West Milford police fire investigator and county prosecutor's arson unit was continuing.
ALL PHOTOS: Upper Greenwood Lake Volunteer Fire Company 5
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