The central and Hong Kong governments have condemned the attack on Beijing's liaison office and the defacing of the national emblem on Sunday evening, saying the actions were a direct challenge to national sovereignty.
A Hong Kong government spokesman said the authorities will follow up the matter seriously.
The spokesman also said it was worrying that a small group of radical protesters had been inciting the crowd to challenge law and order with plans to even storm the liaison office.
He said the protesters' actions posed a threat to the territory's law and order and "One country, Two systems". He said society would not accept this.
The liaison office also issued a statement, saying the protesters had challenged the bottom line of the "One country, Two Systems" principle and the authority of the central government.
A spokesman for the office said it supports the SAR government and the police punishing those responsible in accordance with the law to safeguard the stability of society.
He stressed the liaison office carries out its duties in strict accordance with the national constitution and the Basic Law and cannot be challenged.
Former Chief Executive CY Leung, now a vice-chairman of Beijing's top advisory body, the CPPCC, also condemned the protesters, calling them mobs that must be punished by the law.
Last updated: 2019-07-21 HKT 23:08
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