Image copyright Getty Images Image caption The Ukraine conflict has made Poland nervous about its eastern borders

Poland has arrested a Russian woman suspected of working with accomplices to foment tension with neighbouring Ukraine, Polish security officials say.

Poland's internal security agency, the ABW, said "Yekaterina C" would be expelled soon. Four other people are now barred from entering Poland.

ABW spokesman Stanislaw Zaryn said the agency had "neutralised" two "Russian hybrid war networks" targeting Poland.

"Hybrid" war includes spreading fake news to change public attitudes.

Poland has been on high alert for Kremlin attempts to influence Polish opinion since Russia annexed Ukraine's Crimea region in March 2014.

Poland - a member of the EU and Nato - is one of the strongest critics of Russian foreign policy, especially Russia's military intervention in Ukraine.

But scars also remain from Polish-Ukrainian hostilities dating back to the Soviet period and World War Two.

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Mr Zaryn, quoted by Radio Poland, said the ABW had information that Russia was "not only inspiring Polish citizens to take specific actions against Poland and in the interests of Russia, but also financing their activities".

He did not give details of the alleged networks' activities. He said they were engaged in "fuelling Polish-Ukrainian animosity in the social and political sphere and undermining the interpretation of Polish history, replacing it with a Russian narrative".

Western governments accuse Russia of spreading fake news about the Ukraine conflict and other sensitive issues, in order to weaken public support for EU and Nato policies.