The official Korean Central News Agency said the performers on Monday showed "beautiful and graceful rhythmic movements, high-spirited gymnastics, interesting national emotion and rich artistic depiction", but also that Kim Jong Un was quite unhappy about their display.
South Korea's conservative Chosun Ilbo newspaper last week cited an unidentified source to report that Kim Jong Un had ordered his sister to lay low following the collapse of his summit with Trump in February over mismatched demands in sanctions relief and nuclear disarmament.
North Korean leader Kim Jong-Un's sister has appeared in public for the first time in nearly two months and shortly after a South Korean report that she had been temporarily demoted following the failed Hanoi summit, state-media media reported on Tuesday.
In one of the images, Mr Kim appears to be covering his face as the other onlookers - including Kim Jong-un - smile and clap.
South Korean media and the government in Seoul have alleged purges in the past, only for the individuals to turn up alive and still alongside Kim Jong-un.
- Adam Cathcart (@adamcathcart) June 2, 2019South Korean Claims Fall Flat? Cheong said it would not make sense for Kim Jong Un to execute Kim Hyok Chol when Kim Yong Chol, the more senior official, would be seen as more responsible for the failure in Hanoi.
Rumors of Kim Yong Chol's demotion have circulated since he failed to accompany Kim Jong Un to Vladivostok to meet Russian President Vladimir Putin last month, an unusual occurrence for a man who is normally not far from his leader's side on foreign trips.
The newspaper also reported that Kim Hyok Chol, the counterpart of USA envoy Stephen Biegun in pre-summit negotiations, had been executed, although many diplomats and experts expressed caution or outright skepticism about that claim.More news: 'Jeopardy!' legend Ken Jennings reacts to James Holzhauer's shocking defeat
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He travelled to the USA in January to prepare for the second summit meeting between Mr Kim and President Trump, which was held in Vietnam. An invitation to join to join the North Korean leader in public would likely not be extended to someone who had fallen out of favor.
The newspaper also reported that Kim had punished his former top nuclear envoy, Kim Yong Chol, who North Korean media showed at the mass games and at a weekend concert of military wives.
The reports on the fate of Kim Yong-chol come at a delicate time for diplomacy as North Korea in past weeks has tested short-range missiles and issued belligerent rhetoric towards American and South Korean officials.
"I wouldn't be surprised if he was demoted", North Korea expert Andrei Lankov of Seoul's Kookmin University told the BBC.
Kim Hyok-chol and the other officials who were reportedly executed have been out of the public eye since the summit in February, but their deaths have not yet been verified.
Accurately tracking palace intrigue in North Korea is a tricky business.
AFP with additional input by GVS news desk.
An analyst at South Korea's Sejong Institute, Cheong Seong-Chang, said that Kim Yong Chol would not have reappeared in public so quickly if he were sent to re-education or forced labor, according to USA Today.