A sign is pictured during a protest to commemorate the victims killed by the neo-Nazi group National Socialist Underground (NSU) during a demonstration at Berlin's Kreuzberg district May 6, 2013. The surviving member of NSU, including Beate Zschaepe, blamed for a series of racist murders that scandalised Germany and shamed its authorities goes on trial on Monday in one of the most anticipated court cases in recent German history. The sign reads "NSU series of murders: pending questions. Bomb attack in Cologne/Keupstreet. Where does the explosives come from ?" REUTERS/Fabrizio Bensch (GERMANY - Tags: CIVIL UNREST CRIME LAW POLITICS)