A late-night fire at an MSU-Mankato frat house on Tuesday has been deemed suspicious in nature. Authorities responded to the fire call at the Phi Kappa Psi house on Lincoln Street in Mankato at just after 2:30 Tuesday morning. Six people were in the home at the time, and were able to extinguish the flames on the front porch without any injuries. Damages have been estimated at $3,000, and investigators say that the cause of the fire is suspicious. No ignition source has been discovered at this time. An investigation continues, and anyone with information is asked to call (507)387-8577.