The army has yet to find a way to contact a driver at its transport department, who is suspected of hacking the personal data of 55 million Thais, according to an army spokeswoman.
Maj Gen Sirichan Ngathong yesterday denied the army was procrastinating on a warrant for the arrest of the sergeant major.
Army investigators had approached his supervisors and family but the suspect could not be reached.
She was responding to a report that police wanted the suspected hacker identified as "SM2 Khemarat" to surrender within seven days.
On Saturday, national police chief Pol Gen Damrongsak Kittiprapas ordered the Cyber Crime Investigation Bureau (CCIB) to bring in the military hacker who claimed to have obtained the personal data of 55 million Thais.
Pol Gen Damrongsak assigned CCIB commissioner Pol Lt Gen Worawat Watnakhonbancha to work with the suspect's supervisor and the army staff judge advocate to try bring him in.
The army has also formed a committee to consider disciplinary measures to take against the sergeant major for tarnishing its image, Maj Gen Sirichan said.
"It is personal wrongdoing and has nothing to do with his military service as a driver," the spokeswoman said, referring to a report that SM2 Khemarat worked at the Army Transportation Department in Nonthaburi province.
Responding to reports that he was being supported by an influential person, Maj Gen Sirichan said that no soldiers suspected of wrongdoing would be protected.
The suspect, using the pseudonym "9Near", posted on BreachForum that he held the personal data of 55 million Thais, including names, surnames, addresses, birthdates, ID card numbers and telephone numbers.
The hacker last week threatened to expose the information if the government agency allegedly involved in the data breach failed to meet a ransom demand.
Reports said the suspect's wife is a nurse who is now on the run with her husband.
She reportedly gained access to data collected by the Mor Prom app, a health service portal of the Public Health Ministry that contains information about many Thais.