18-year-old arrested for deadly shooting in Irmo 18-year-old arrested for deadly shooting in Irmo By Laurel Mallory and Lauren Adams | February 25, 2021 at 1:19 PM EST - Updated February 26 at 10:34 PM IRMO, S.C. (WIS) - An 18-year-old man faces murder charges after a deadly shooting in an Irmo neighborhood, the Richland County Sheriff’s Department confirmed. Deputies say James Thompson III, 18, accidentally shot himself before fatally shooting the other man during an argument. (Source: Alvin S. Glenn Detention Center) The shooting happened around 9 a.m. Thursday in the front yard of a home on Walnut Grove Circle, deputies said. That’s in a neighborhood off Shady Grove Road near Interstate 26, about a mile from Dutch Fork High School.