Police shut down the museum in August and confiscated four paintings, including one depicting President Vladimir Putin and Prime Minister Dmitry Medvedev in women's clothing, the Russian news agency RIA Novosti reported.
The museum reopened Thursday without the confiscated artworks, and the theft was noticed a day later, Alexander Donskoy, museum owner and former mayor of the Arctic city of Archangelsk, said.
Donskoy added he would not report the theft to the police, saying ironically, "Art must belong to the people."
Friday was the final day of the museum at the building in central St. Petersburg, Donskoy said, noting the building's owner had asked him to move out.
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