 The opening was marked by a three-day protest by the anti-capitalist Blockupy movement, an offshoot of the Occupy movement, and other opponents of the European troika, and by violence across Frankfurt on the opening day.Police used water cannons and tear gas against protestors, while demonstrators threw stones at police, firefighters and Frankfurt's trams, and set fire to cars and barricades.The ECB's new headquarters was reportedly selected as the venue for the demonstration so as to highlight the contradiction between the ECB's lavish spending on its own US$1.4-billion building while forcing cuts and market reforms on countries like Greece and Cyprus.