Sources in the country's Ministry of the Interior have told BNS that the Russian national was declared persona non grata in Lithuania in August.
Sapozhnikova told BNS on Tuesday she had learnt about it on August 26 after flying to Vilnius from Tallinn.
In her words, the provided document stated that she had been banned from entering Lithuania for five years.
Lithuania's State Security Department said in a report last year that Sapozhnikova, a resident of Tallinn and Moscow, had founded an international media club Format-3 which was spreading "Russia's political and ideological provisions" in the Baltic states and that 11 events were organized in Lithuania in 2013 alone, attended by pro-Russian political scientists, economists, writers and culture representatives.
Estonia's intelligence also mentioned Sapozhnikova in its 2009 report as one of the founders of the Impresum press club which, the Estonian security police said, was engaged in anti-Estonian propaganda. It invited speakers who supported the Kremlin's policy and were nostalgic about the Soviet Union.