The suspect, a foreign citizen, was detained on March 21, according to a statement released on Monday.
"The findings made in the case show that the suspect acted for the benefit of Russian intelligence by obtaining and collecting information ... on critical infrastructure in the Pomorskie and Kujawsko-Pomorskie regions and on the activities of services and bodies responsible for security," prosecutors in the northern Polish city of Gdańsk said.
"The information obtained was passed on to the Russian intelligence service," they added.
The court has ruled to detain the suspect for three months, the Polish government said.
The man has confessed to spying and provided details of his activities, as well as of how he had been recruited by Russian intelligence, according to Polish officials.
He had been working for Russian intelligence at least since January, reporters were told.
If found guilty the suspect could face up to 10 years in prison, the Reuters news agency reported.
Poland targeted by foreign espionage
Monday’s announcement marks another detention of a person on espionage charges, the PAP news agency reported.
On March 1, Poland detained another foreign national, on suspicion of spying for Russia’s ally Belarus, officials said.
According to the evidence gathered, “the suspect had been conducting reconnaissance of facilities of importance to Poland’s national security, including facilities related to the Polish armed forces,” the government said.
A court in the eastern city of Lublin ruled to detain the man for three months, according to officials.
Monday’s announcement comes after Poland dismantled a Russian spy network that had been preparing acts of subversion and monitoring rail routes to Ukraine, according to officials.
The war in Ukraine has plunged what were already strained relations between Poland and Russia to new lows, with Warsaw saying it is frequently the subject of Russian espionage and disinformation, Reuters reported.
Since Russia invaded Ukraine in February 2022, Poland has detained 20 people on suspicion of spying for Russia or Belarus, the PAP news agency reported.
Last month, a Russian national who had been living and doing business in Poland for many years was charged with spying for Russia between 2015 and 2022. He faces up to 10 years in prison.
Hackers attack website of Polish counterintelligence agency: spokesman
Stanisław Żaryn, a spokesman for Poland’s security services, said on Monday that the website of Poland’s Military Counterintelligence Agency (SKW) recently became the target of a hacking attack.
He said the SKW’s website “was recently unavailable for a short period of time” due to a so-called distributed denial-of-service attack (DDOS).
Żaryn said the website was quickly restored and suggested the attack could be seen as “an attempt to respond to the effective activities of Polish counterintelligence services.”
He told reporters that, in recent months, "both the Internal Security Agency (ABW) and the SKW have been very effective in neutralising successive actions of Russian intelligence against Poland.”
Monday is day 397 of Russia’s war on Ukraine.
Source: IAR, PAP, gov.pl