Hotel / Restaurant, Restaurant Mankato, MN – Sprinkler system activates to help control lunch-time restaurant fire March 29, 2015 viking210 Investigators have determined the cause of Wednesday’s fire at Asiana Buffet in Mankato. Fire officials say the fire originated in a wok in the kitchen. The fire then spread to the restaurants ceiling. The fire started over the noon hour and officials say firefighters were notified of the fire by a sprinkler alarm. When firefighters arrived, lunch-hour diners and staff were still in the restaurant, most unaware that a fire was spreading in the ceiling and rafters. Staff was apparently trying to fight the fire and it eventually triggered a sprinkler system that alerted the fire department. Damages are estimated at $1.75 million.There were no injuries.