More than 80 firefighters responded to a Silver Spring house fire Friday night but were unable to rescue the man inside.

Montgomery County Fire and Rescue Service arrived at a two-story home on Lorain Avenue just before 9:30 p.m. and found flames coming from the second floor. The resident, whom officials did not identify Saturday, was discovered in an upstairs hallway, already deceased. No others were known to live at the home.

The fire was so large that it took over an hour to bring under control. Fire and Rescue Service spokesman Pete Piringer said hoarding-like conditions inside the home fueled the blaze. Although the bedroom was determined to be the location of the fire’s origin, it remains unclear whether cigarettes, electronics or some other hazard was to blame.

“A definitive ignition source cannot be concluded,” Piringer said. “The cause of the fire is officially undetermined.”