Hundreds can be constituted-of-or-filled-with (riot police officers).Logical formLearned from26 sentences. Riots may break_out in a US-city.Logical formLearned from26 sentences. Riots can be black.Logical formLearned from26 sentences. Youths may clash with (riot police).Logical formLearned from26 sentences. (Riot police) may pertain-to an international-political-entity.Logical formLearned from26 sentences. Police can be with (riot gear).Logical formLearned from26 sentences. Riots can be by youths.Logical formLearned from26 sentences. Riots can be in jails.Logical formLearned from26 sentences. Cordons can be constituted-of-or-filled-with (riot police).Logical formLearned from26 sentences. (Riot police) can be with batons.Logical formLearned from26 sentences. Riots may be flared.Logical formLearned from26 sentences. A role can be in a riot.Logical formLearned from25 sentences. Riots can be in a country.Logical formLearned from25 sentences. A riot can be in a world-city.Logical formLearned from25 sentences. (Riot police) may clash with demonstrators.Logical formLearned from25 sentences.