Kim Yo-Jong attended the opening ceremony of the PyeongChang Winter Olympics in South Korea on February 9.
A spokesman of the Korea Asia-Pacific Peace Committee said in a statement that Mike Pence's speech was a "disgraceful behaviour" and "an act of rogue without an equal in the world", Xinhua news agency reported on Sunday.
Mr Pence, who also attended the opening ceremony of the games, reportedly said at a conservative group meeting in Maryland state in the US on February 23 that Kim Yo Jong, who is officially a first vice department director of the Central Committee of the Workers' Party of Korea (WPK), is "the centre of a vicious regime" and "a central pillar of the most tyrannical and oppressive regime on the planet".
He said North Korea's army and people are "sharing their destinies with their leader and their social system to find out and punish without mercy those insulting the dignity of the supreme leadership and the social system of North Korea no matter whoever and wherever they are."
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