Waterloo Regional Police are investigating after a man was shot in Waterloo early Sunday. Police said officers responded to reports of a shooting on Marshall Street at about 12:15 a.m. Officers located a 31-year-old man suffering from a gunshot wound. He was taken to hospital with serious but non-life-threatening injuries. Investigators believe the people involved were known to one another. Police said the investigation is being led by the General Investigations Unit and that there will be an increased police presence in the area as officers canvass for witnesses and gather additional information. Anyone with information or who witnessed the incident is asked to contact Waterloo Regional Police.