Political activists are pushing for an investigation into what they describe as the army's administrative errors, which they believe was the root cause of the massacre in Nakhon Ratchasima last weekend.
The mass shooting on Feb 8 at a shopping mall left 30 dead, including the shooter, and 58 injured.
The People's Party for Freedom, Democracy Restoration Group (DRG) yesterday submitted an open letter to the House of Representatives' committee on military affairs demanding an investigation into the army's alleged mismanagement.
In the letter, the group pointed out flaws in the security of the army's armouries, from where the soldier had stolen weapons before going on the shooting spree.
The letter said the gunman had spent nearly an hour helping himself to weapons from several spots in the military camp without any alarms sounding.
It also added that businesses run by the army, especially those managing army-owned land for commercial purposes, need to be investigated.
The activists are also demanding that the authorities look into certain members of top brass, who have abused their authority for the benefit of themselves and their families.
The military housing project, for instance, in which the gunman was reportedly cheated by his superior and his superior's family, was clear evidence of blatant abuse in the army, the letter said.
The activists want the army chief to be held responsible for these problems.
Separately, in a Facebook post, activist Srisuwan Janya said he will today call on the Ombudsman and urge him to look into the military's rules, regulations, work procedure and chain of command, which he believes are flawed and one of the major factors leading to the shooting spree.
A revamp is required to rebuild the military's integrity and reputation, as well as prevent a repeat of the tragedy, he said.
Mr Srisuwan said he will also ask the Ombudsman to look into Prime Minister Prayut Chan-o-cha's faux pas when he visited those affected by the shooting. The PM waved, smiled and made a mini heart -- gestures that were totally inappropriate given the situation, Mr Srisuwan said.
Chumsai Siyaphai, a deputy spokesman for the opposition Pheu Thai Party, also demanded that Gen Prayut fire army commander Apirat Kongsompong over the mass shooting.
Gen Apirat, meanwhile, has told the Army Welfare Department to speed up a survey on army housing, some of which is being occupied by retired officers, a source said. The army chief has also reportedly ordered retired officers to move out so incumbent officers can take up residence.
The army chief said exceptions have been made for some retired top brass, provided they have contributed to the country in their high-level positions.
These retirees include Gen Prayut and other ex-army officers who currently serve as cabinet members, senators and Privy Council members.