A portion of County M is closed to traffic after Rock County sheriff’s deputies surrounded a house mid-morning for an apparent standoff. Sheriff Robert Spoden says people in the house are persons of interest in a convenience store robbery overnight in Janesville. The closure is between Pine and Newville Roads. Sheriff Spoden says a domestic violence victim escaped the rural residence and told deputies that one of two people inside the house had fired one shot. The county SWAT team was being called out, just in case. Janesville police say officers responded to an armed robbery at Stop N Go on Center Avenue aobut 1:30 Thursday this morning. Police say the robber, described as a black female a little under five-foot six, and waring a black hooded sweatshirt and black sweatpants, left the store heading west on foot with cash and Newport 100 cigarettes. The clerk was not hurt.