The Department of Special Investigation (DSI) has accepted the purchase of GT200 bomb detectors and the state issuance of fake identity cards as special cases.
The cases were approved because of their severity and complexity, following a review yesterday by the DSI's special case panel, chaired by deputy Prime Minister Pracha Promnok.
In the GT200 case, state agencies were found to have bought substandard bomb detectors from a firm engaging in "cheating behaviour", Pol Gen Pracha said.
Thirteen agencies are believed to have been duped into buying 1,300 bogus bomb and drug detectors from UK-based Comstrac Co, owned by James McCormick, according to the DSI's initial investigation.
McCormick was sentenced to three years in jail earlier this year by the Central Criminal Court in London which found him guilty of selling detectors that did not work.
The Thai army, the biggest buyer of the GT200s, mostly used the devices in the restive far South.
In the fake ID case, the DSI found some registrars in Chiang Mai's Mae Taeng district had allegedly re-issued identity cards illegally to people whose names had been withdrawn from the district's registration list, Pol Gen Pracha said.
Up to 850 stateless people were handed fake ID cards between 2009 and 2012, according to the DSI.
The DSI suspects the officials were part of a criminal enterprise that involved "large amounts in kickbacks", Pol Gen Pracha said.
A crime like this is considered a threat to national security, he said.
Meanwhile, the DSI will on Monday send prosecutors its report on the sex allegations that have been laid against Wirapol Sukphol, the former monk known as as Luang Pu Nen Kham, DSI chief Tarit Pengdith said.
Mr Wirapol has been accused of having sex with women, including an underage girl, while he was still a monk, among other charges against him. The allegations led senior monks to defrock him.