Kiev 's police chief resigned after riot police violence against protesters , protesters say . Others broke through a police barrier that was guarding a Christmas tree , climbed the tree and topped it with the Ukrainian flag . Anti - government demonstrators continue to clash with security on Sunday . Interior Ministry calls for violence , but urges police to cooperate .
Kiev 's police chief resigned after riot police violence against protesters , protesters say . Anti - government demonstrators continue to clash with security on Sunday . Interior Ministry calls for violence , but urges police to cooperate .