Janesville police are investigating the cause of a fire at Texas Roadhouse overnight. According to a news release, the Janesville Fire Department responded to the Texas Roadhouse in the 3200 block of Deerfield Drive around 12:15 a.m. Friday for a report of a commercial fire. Responding units said they found an active fire and smoke visible in the front of the building when they arrived at the scene. According to fire officials, the first engine to arrive was able to confine the fire to the exterior of the building’s front. A sprinkler was able to contain the fire inside the building until firefighters were able to extinguish it.