The State Fire Marshal’s office said a Richmond man was seriously injured in an apartment house fire in downtown Richmond early Christmas morning.

Wade Welner, 30, is being treated for smoke inhalation at Maine Medical Center.

He was rescued from his second-floor unit at 34 Main St. by a Richmond police officer.

The only other occupant of the building, who heard the alarms, escaped unharmed, fire officials said.

The second floor of the building was destroyed, and fire investigators are working to determine the cause.