A soldier has killed 20 people and injured dozens more in a gun rampage in the Thai city of Nakhon Ratchasima.
Jakraphanth Thomma, a junior officer, killed his commanding officer before stealing weapons from a military camp.
The suspect continued his attack in a shopping centre, where he is now believed to be holed up, initially posting updates on his social media.
Security forces are in the complex and have rescued hundreds while searching for the gunman, with shots ringing out.
The gunman's motives remain unclear.
Authorities sealed off the Terminal 21 shopping centre in Nakhon Ratchasima, also known as Korat, on Saturday evening.
Troops and police officers entered in order to search for the suspect and help those trapped inside, with ambulances brought up to the complex to ferry away the injured.
Throughout the evening there were sporadic reports of further gunshots, lasting into the early hours of the morning. The latest appeared to be an attempt by the gunman to escape via the back of the building.