WARSAW (Reuters) – The email accounts of a dozen MPs were recently hacked, Poland’s counter-intelligence said on Friday, revealing further details of one of the biggest cyberattacks on the country in recent years.

The revelations come two weeks after authorities said senior Polish government officials were hit by a large-scale cyberattack in June that affected more than 100 email accounts of current and former government officials.

Among the accounts allegedly hacked was the personal account of prime minister Michal Dworczyk’s top aide, an intrusion that sparked a series of leaks that led to opposition criticism of officials for using accounts private to exchange confidential documents.

In a statement on Friday, counterintelligence authorities said the parliamentarians affected by the hack came from almost all parliamentary opposition groups, and those affected had been briefed and received cybersecurity training.

The statement did not identify the hacked lawmakers.

Polish counterintelligence said on June 22 that evidence showed links between the hackers and the Russian secret service. [L5N2O435W]

He said the attack was carried out by hackers known as UNC1151, adding that the group’s actions were part of a campaign known as Ghostwriter which has targeted Polish politicians in recent months and which has also affected other countries in the region.

The Russian government and the Kremlin have repeatedly denied carrying out or condoning cyberattacks following US allegations of cyberattacks on US territory, Ukraine and Saudi Arabia.[nL2N2NY21J[nL2N2NY21J[nL2N2NY21J[nL2N2NY21J

Poland’s lower house of parliament, the Sejm, was not immediately available for comment.

(Reporting by Joanna Plucinska and Alicja Ptak, editing by William Maclean)

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