Thai National police chief Pol. Gen. Chakthip Chaijinda confirmed on Sunday that a soldier killer who killed at least 22 people in northeastern Thailand late Saturday had been shot dead by authorities.

The 32-year-old gunman, identified as Sgt. Jakrapanth Thomma, killed at least 22 people, including six policemen of the Arintharat police commando unit, and wounded 42 others in the downtown area of Nakorn Ratchasima city, police said.

Public Health Minister Anutin Charnvirakul pleaded for blood donation to save the more than 40 injured who were being treated in hospital.

Thai Prime Minister Prayut Chan-o-cha will be arriving at Nakorn Ratchasima on Sunday after the deadly shooting rampage.