They "ran around like headless chickens, barking that "the ship of reds came, 'go back to your country" and 'boost the south Korea-U.S. alliance, ' " the state-run North's Korean Central News Agency said.
"Earlier, however, US Secretary of State Rex Tillerson did not rule out a possible meeting between Vice President Mike Pence and North Korean representatives during his upcoming trip to South Korea".
Tensions soared past year as the North carried out multiple weapons tests, including intercontinental ballistic missiles capable of reaching the United States mainland, and by far its most powerful nuclear test to date.
"The military personnel ... will be responsible for security checks of the 20 venues as they take up jobs such as security searches, previously done by civilian safety personnel, until the patients' condition is normalized", a statement from the South Korean Olympic committee said.
Pence has voiced scepticism that the North, which is participating in the Games, will use the event for crude propaganda.
Pence arrives in South Korea on Thursday after visiting a missile defense base in Alaska and American military bases in Japan.
Some were carrying pictures of North Korean leader Kim Jong-Un with a huge X across his face while others crumpled the images and stamped them underfoot.
Officially the delegation will be headed by Kim Yong-Nam, who leads the presidium of the Supreme People's Assembly, the North's rubber-stamp parliament, and will attend the Games' opening ceremony.
The ministry said Kim Yo Jong's schedule in the South has yet to be determined, and it wasn't immediately clear whether she will meet with President Moon Jae-in, a liberal who has expressed a desire to reach out to the North. She was promoted to the ruling party's executive committee a year ago. The development has raised hopes of reconciliation in the troubled Korean peninsula. In fact, North Korea tested its first nuclear weapon eight months after the conclusion of the 2006 Winter Olympics.
North Korea test-fired ballistic missiles over Japan previous year, as well as a new type of intercontinental ballistic missile that climbed to an altitude of more than 4,000 km (2,485 miles) before splashing into Japanese waters. "My message - whatever the setting, whoever's present - will be the same".