The long-serving Polish defence ministry worker was detained last Tuesday following a months-long counterintelligence investigation.
Brigadier General Jarosław Stróżyk, head of SKW, told the Polish Press Agency (PAP) the suspect possessed "enormous knowledge useful to foreign intelligence services" and had access to strategic planning throughout his career, which began in the early 1990s.
The charges concern acting on behalf of a foreign intelligence service from the "eastern direction" and passing on information that could harm Poland, an offence carrying a potential sentence of eight years to life in prison.
On Wednesday, a court ordered the suspect to be held in pre-trial detention for three months.
Security access and senior roles
The defence ministry employee had access to classified materials and last underwent vetting in 2021.
"We are dealing with a person who over all these years has met thousands of people, including those in the most important official positions," Gen Stróżyk said.
He pointed out that the suspect had served "in the ministry’s key departments dealing with strategy, defence planning and international security".
The SKW chief described the arrest as an "undeniable success" for Polish intelligence services.
He dismissed claims the suspect was detected simply because he failed to return from a trip to Belarus, calling such suggestions disrespectful to his officers' "hard and long-term work".
Investigators are examining all the suspect's data devices and have not ruled out the possibility of a wider spy network.
Gen Stróżyk said Polish law may need to allow for restrictions on foreign travel by senior defence officials.
Polish Parliament's intelligence committee is due to receive a classified briefing on the arrest.
(ał)
Source: PAP