WARSAW, Poland — A group of hackers that associates itself with the Ukrainian far-right political party Right Sector claims it has gained access to the servers of Poland's Ministry of Defence, from where the group alleges to have collected classified information.

The Polish ministry said the information was not classified, and it is currently investigating the alleged cyberattack.

"Regarding the information on a break-in to the computer network of the Polish Ministry of Defence, we clarify that it was a manipulation designed to create an impression of a dangerous cyberattack," Bartlomiej Misiewicz, the ministry's spokesman, said in a statement.

Misiewicz said both the ministry's and the military's command and control systems were intact and fully secure. The stolen personal information was available in the ministry's non-classified databases, related to one person, he said, adding that the databases have not been updated since 2012.

On July 14, the group posted screen shots and excerpts of the allegedly hacked materials on its Twitter account, threatening that if the Polish government does not pay the hackers US $50,000, "we will publish all the logs … within few hours."

Right Sector is a nationalist party that was initially set up as a paramilitary organization. While it has helped the Ukrainian government in combating pro-Russian separatists in the country's east, it has also protested against Ukraine's closer cooperation with NATO and the European Union and carried out violent protests against political opponents.

Jaroslaw Adamowski is the Poland correspondent for Defense News.

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