I don't think MS13 was involved, but we can't rule out cartel operatives. They exist all over the United States and wouldn't give a second thought to killing someone in a way that sends a message. Not saying it's a likely scenario, but something that can't be dismissed. As this article shows, there are plenty of illegal immigrants living in the Jackson, MS area: http://www.clarionledger.com/story/news/...inees/98294230/

But the place to start would be with finding out more about the victim. Right now they don't even know if the head matches the body (I'm guessing that they probably will determine the head and torso both belong to Jeremy Jackson). Who were his associates? Was he involved in a gang or drug trafficking, or some other illegal activity? If he was, did he step on anyone else's toes or encroach on territory -- or did someone else try to take over his territory? Or maybe he was a witness and confronted someone he shouldn't have. Whatever the reason, he clearly pissed off someone severely enough to want to murder him and send a message.