Commanding officer of Marine Regiment , second the 1st Battalion will be reassigned . Three Marines were killed in a mortar range accident in March . After the accident , the Marines discontinued use of the 60mm rounds and mortar tubes , but the Marines statement said a preliminary investigation determined the mortar system `` functioned properly '' at the site of the explosion . Marines statement says system appeared to work properly .
Commanding officer of Marine Regiment , second the 1st Battalion will be reassigned . Three Marines were killed in a mortar range accident in March . Marines statement says system appeared to work properly .