The commandant of the Marine Corps has an important message regarding the Wednesday's mass shooting in a California bar: Marines don't murder innocent people.

Marine Commandant Gen. Robert Neller condemned the “despicable actions” of Ian David Long, the 28-year-old Marine veteran who shot and killed 12 people at a bar in Thousand Oaks, California, on Wednesday, in a Thursday tweet:

Note the use of “ex-Marine” instead of “former Marine” here. That, according to Corps officials, was a deliberate dig at Long.

“They say 'once a Marine, always a Marine' because the title of Marine is something you earn. You can give it away, and you can walk away from it in your actions and deeds,” Marine Corps HQ spokesman Lt. Col. Eric Dent told Task & Purpose. “This is by deed.”

“This guy presumably murdered people,” Dent added. “That's not what Marines do.”

The vast majority of veterans go on to serve honorably after they leave the U.S. armed forces, Dent explained, applying their military experience to the benefit of their community and country. Long, in the eyes of Corps officials, did the complete opposite.

“The message when we choose 'ex' over 'former' is that you walked away from all those things that make us stronger together, that make us a family,” Dent said. “When you do these despicable things, you're not doing them as a Marine.”

SEE ALSO: Marine Veteran Among Dead In Thousand Oaks Mass Shooting