Leader of the Young Russia movement Anton Demidov, center, holding a portrait of Nefteyugansk mayor Vladimir Petukhov, who was allegedly murdered by the former head of the internal economic security department of Yukos Oil company Alexei Pichugin, convicted of the crime. The man was detained at an unauthorized picket on Tverskaya Boulevard, where an opposition rally marking the birthday of former Yukos CEO Mikhail Khodorkovsky was authorized by the city.