The last siege of the Kremlin in Moscow was in the early 17th century, ironically by a Polish claimant to the Russian throne, the False Dmitry, as defender and the Russians as besiegers. What did the Russian besiegers do to Dmitry when the Kremlin finally fell?
Answer: The Russians executed Dmitry, burned his body, primed a cannon on the Kremlin wall and fired his ashes back toward Poland.
Source: Peter the Great – His Life and World by Robert K Massie