The governor and police in Nakhon Ratchasima province are scurrying to shed light on the disappearance of about 100 M16 rifles from a defence volunteer arsenal in 2011, a loss that only recently came to light.
The weapons were kept at the depot of a battalion of defence volunteer forces under the Interior Ministry in Muang district of the northeastern province before they went missing.
All defence volunteers at the barracks are being interrogated and governor Thongchai Leu-adul has set up a special panel to look into the disappearance of the weapons in 2011, a move that drew the attention of the Royal Thai Army.
Army commander-in-chief chief Gen Udomdej Sitabutr said in Bangkok that soldiers had been directed to help the investigators. Troops from the 2nd Army Region based in Nakhon Ratchasima had now joined police and provincial authorities on the case.
Authorities in Nakhon Ratchasima have been unable to explain where the assault rifles have gone, and why attempts to trace them have progressed so slowly.
The governor said only that the case had been with police ever since officials found out the weapons were not in the battalion depot, where they were supposed to be. However, reports said the complaint was registered only in May, after an internal investigation by provincial authorities went nowhere.
"Anybody involved in the theft of the weapons will be strongly punished and face both disciplinary and criminal charges," the governor warned.
Mr Thongchai was appointed governor in June last year. There have been three other governors before him since 2011.
Pol Maj Gen Pakorn Sermsuwan, the chief investigator of the Provincial Police Region 3, said 14 of the rifles have been tracked to defence volunteers who took them out and did not return them.
Pol Maj Gen Thaokrn Nutthisri, the provincial police chief, said it will take investigators some time to solve the mystery of where the missing guns went.
Revelation of the weapons' disappearance raised speculation they could have been used for political violence.
However, Pol Col Somsak Ruekputthi, superintendent of Jorhor police station where the battalion is based, brushed the speculation aside.
An initial police investigation pointed to the ignorance of the defence volunteers in charge of the depot, as they allowed the weapons to be taken out with no written records, he said.
Authorities are now checking on all rifles issued to armouries for use by defence volunteers in all districts of the province.