Waterloo Police are investigating a bullet hole and a blood trail found in a vacant home found on Friday, according to the Waterloo Cedar Falls Courier. The bullet hole was found in a home at 412 Sunnyside Avenue. In addition, four shell casings were located and a blood trail was found in the middle of the road. Police have not confirmed the circumstances surrounding the incident and cannot confirm that the blood trail and the shots fired are related. The investigation is still ongoing at this time.