Sergeant Major Yongyuth Mungkornkim, a clerk at the Royal Thai Army War College, will stand trial in a military court on Wednesday in the north of Bangkok.

He faces charges of premeditated murder, attempted murder, possessing a gun in a public place and firing a gun in a public place.

National deputy police spokesperson Kissana Phathanacharoen told AFP the military court would decide whether or not to grant bail.

Yongyuth's mental and physical health was being assessed by medical professionals at a hospital, said Kissana.

Police investigators have 84 days to conduct their investigation and report on the case before forwarding documents to the military court's attorney, he added.

In the past year, there have been at least two other fatal shooting incidents by serving soldiers, according to the Bangkok Post.

And in 2020, in one of the kingdom's deadliest incidents in recent years, a soldier gunned down 29 people in a 17-hour rampage and wounded scores more before he was shot dead by commandos.