MITCHELL, S.D. (MITCHELLNOW) A gas leak in Mitchell on Sunday afternoon prompted a response from fire crews but caused no injuries. Officials say the leak happened at High Plains Processing after a lawn mower struck a gas line. Firefighters worked with plant staff and Northwestern Energy crews to shut off the valve and secure the area. Mitchell Fire Department crews also went door-to-door at nearby homes, offering residents gas detectors as a precaution. For more Government stories from MitchellNow.com, Click Here.