Arpo pointed out that Estonian law states very clearly the conditions which rule out security clearance being granted to an individual. The ISS also has discretionary power where these points are concerned, as not all cases are absolutely clear.

A complicating matter is the fact that any of their decisions can be contested in court. "If there are no circumstances as listed in the law that rule out granting access, it is possible to take the matter to court," Arno pointed out, adding that in such a case the ISS' own reasons to refuse access are put in question.

"But once again, the principles on the basis of which it is possible to refuse access to state secrets are listed in the law, and we can't improvise or make decisions based on just a gut feeling," he stressed.

Arpo confirmed that Maj. Deniss Metsavas, who is under arrest for suspicions of having passed on state secrets to Russian military intelligence, had received security clearance also at the time that he was allegedly passing on information to the Russian military intelligence service GRU.

Defence Forces commander: Military staff in state of shock

Commander of the Estonian Defence Forces (EDF) Gen. Riho Terras, who also appeared on the program, said that the EDF's staff is in a state of shock following the incident.

Asked about Metsavas' earlier and very patriotic statements eg. on ERR's Russian TV channel, ETV+, Terras called Metsavas a "scoundrel" and said that such duplicity is "amazing."

Officials announced on Wednesday that the Harju County Court on Tuesday decided to have Deniss Metsavas, born 1980, and his father, Pjotr Volin, born 1953, arrested on suspicions of treason.

The men are suspected of having forwarded Estonian state secrets and classified external information to the Russian military intelligence agency GRU.

According to the investigation, the suspects did so over a period of at least five years until the arrest of the men as suspects on Tuesday.

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