According to reports, the man first shot his commander dead and two others at a military camp before hijacking a Humvee and starting shooting at civilians in a shopping mall in the Mueang district of the city.
The gunman was identified by police as Sergeant Major Jakapanth Thomma.
Law enforcement has advised people to avoid the area where the event took place..
Videos that emerged on social media allegedly show the shooting incident.
#Thailand 🇹🇭 soldiers in the streets of in Nakhon Ratchasima, ongoing operation to arrest a rogue soldier who went on a shooting rampage— Saad (@SaadAbedine) February 8, 2020
They want to secure the release of the hostages he is holding on the 4th floor of the mall https://t.co/BYv7VlEzYl https://t.co/jJbCcbwVrC pic.twitter.com/NK4CYZrZCQ
Video shows Thai soldier Sgt. Jakkrapanth Thomma inside Terminal 21 shopping mall in Nakhon Ratchasiman during his shooting rampage that killed at least 12 people. #Korat #Thailand pic.twitter.com/vQg3ABSnqn— ISCResearch (@ISCResearch) February 8, 2020