Manhattan Firefighters were called out for the second time in a 12 hour time period, shortly before 11:30 Monday night, for a structure fire at 831 Colorado Street. Upon arrival, crews found a single story residential structure with smoke and fire showing from the rear area of the structure. Six fire apparatus and seventeen firefighters initially responded to the fire and it was contained within twenty minutes.The structure was vacant at the time of the fire. The owners are listed as Ben and Ralph Nyberg of Manhattan.Fire crews were still on the scene a couple of hours later extinguishing hot spots and performing overhaul. The fire cause is under investigation at this time.