At least 17 people were killed and 21 wounded in a shooting by a soldier in the north-eastern Thai city of Nakhon Ratchasima, a police spokesman said in a message sent to reporters yesterday.
Police identified the suspect as Jakrapanth Thomma. He had posted on his Facebook page earlier in the day that "Death is inevitable for everyone".
He also posted a picture of what appeared to be his hand holding a gun.
At one point after the shooting had begun, the suspect posted "Should I give up?" before his account became inaccessible. The soldier opened fire at different locations in the city, which is more than 250km from the capital Bangkok, said the police spokesman.
Local media showed footage of the soldier getting out of a car in front of a shopping mall and firing a series of shots, sending people running.
One video from a bystander showed a man slumped at the wheel of a car in a pool of blood. It was unclear if he was among the dead. Another video showed at least four people who had clearly been shot and showed no sign of movement.