PHOENIX - Investigators are calling an overnight office fire suspicious.
It happened just before midnight on Friday morning near Metrocenter at 31st Avenue and West Peoria Avenue.
Firefighters attacked the blaze from the roof.
Once they got inside, investigators determined the fire started on the second floor inside the elevator shaft.
Many of the offices appear to be vacant.
The building is not a total loss. The damage was contained to a particular area.
Investigators will try to figure out what/who caused the fire.