The correct answer is Islam Karimov, president of Uzbekistan. Farhad Usmanov is a human rights cause celebre in Uzbekistan because his is the most blatant and the most widely protested of many cases of murder of political opponents by the Uzbek regime.
The stickers etc. seem to be the handiwork of the Muslim fundamentalist group Hizb-ut Tahrir, an insidious organisation committed to human rights violations of other kinds (against Jews, gays, women, etc.), but who object to attacks on fellow Islamists and who therefore have a lot of gripes with the Uzbek government. This government is particularly keen on killing Islamists because they happen to be the main opposition force in the country. Farhad was the son of a cleric.