I am not familiar with this incident. One would think it would be pretty well known, from this account. During that time news stories tended to be sensationalized, depending on the editors sympathies. Could be this unit:
John McNeil (First_Last)
Regiment Name 3 U.S. Res. Corps, Mo. Inf. 3 Months, 1861
Side Union
Soldier's Rank_In Colonel
Soldier's Rank_Out Colonel
UNION MISSOURI VOLUNTEERS
3rd Regiment, US Reserve Corps, Missouri Infantry (3 months 1861)
Organized at Turner Hall, St. Louis, Mo., May 8, 1861. Attached to Lyons' Army of the West. Capture of Camp Jackson May 10. Provost duty at St. Louis till July 1. Three Companies sent to Southwest Missouri July 1. Expedition to Northern Missouri against Harris July 16 (7 Cos.). Action at Fulton July 17. Duty at Fulton and St. Louis till August 18. Mustered out August 18, 1861.
Regiment lost during service 1 Enlisted man killed and 8 Enlisted men by disease.