SBU Head Vasyl Hrytsak told journalists, Censor.NET reports.
"According to our information, he was arrested," he said.
According to him, in mid-2014, the detained officer was refused access to state secrets, and has been under SBU's control since late 2015.
Hrytsak added that the officer intended to leave for Russia and filed a corresponding statement. However it was not agreed, and he went there illegally.