Activists of Ukrainian opposition parties clash with riot police as they attempt to get into the mayoral office during a rally against the Kiev mayoral election, which was earlier postponed until 2015, in Kiev October 2, 2013. Ukrainian police used tear gas in the centre of capital Kiev on Wednesday to prevent incursion into the building of the city council of thousands of protesters who believe the current council meeting is illegitimate. REUTERS/Maks Levin (UKRAINE - Tags: POLITICS CIVIL UNREST TPX IMAGES OF THE DAY)