• Shirtless North Korean soldiers faced off against a bed of nails, concrete blocks, and swords in honour of their Supreme Leader on Monday.
  • Their demonstration of strength was part of a defence development exhibition to show off North Korea's military.
  • One man laid on top of glass shards and had a concrete block on his abdomen smashed by a sledgehammer.
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Flanked by charging soldiers, a shirtless man fends off spinning kicks two at a time, throwing his opponents over his shoulder. Then he tenses up, and the soldiers wail on him with poles. He roars in defiance.

On the bleachers, Supreme Leader Kim Jong Un clapped and smirked in approval. The hundred or so uniformed officials around him applaud non-stop.

The staged fight was part of a defense development exhibition in Pyongyang on Monday - a show of the ruling party's strength that included flight stunts by combat pilots, a weapons display, and a series of daring martial feats by the North Korean army, according to state media KCNA.

Soldiers at the exhibition screamed war cries as they barreled through concrete slabs, split rows of bricks in half with their elbows, and performed sprinting dropkicks in a state broadcast that aired Tuesday.

In a video of the broadcast, tweeted by Martyn Williams, a Stimson Center fellow who researches North Korea, the soldiers are seen progressing to acts beyond martial arts, like bending a metal rod with their necks.

Several of the men, all shirtless, lay their arms across what appears to be a stack of tiles, and have their biceps and hands bashed by sledgehammers, cracking the tiles underneath. They strike fighting poses afterward, seemingly unharmed.

One man lies on a bed of nails, then has a concrete block placed on his stomach that gets hammered in half. Another has swords placed on his abdomen, which receives the same block-and-sledgehammer treatment.

In the final segment of the video, a man shatters two bottles over a blanket of glass shards, then lies on top of them. He, too, has a concrete block smashed on his abs.

All the while, a continuous stream of fighting shouts can be heard, though it's unclear if these were added in for the state broadcast or if they were the soldiers making such cries. According to the BBC, the event is the first of its kind since Kim took power in 2011.

At the exhibition, dictator Kim accused the US of sparking hostilities and creating tensions while claiming that North Korea is only looking to defend itself.

"The United States has frequently sent signals that it is not hostile to our state, but its behaviors provide us with no reason why we should believe in them," said Kim during the exhibition, dubbed "Self-Defence 2021," per state media Rodong Sinmun.

The regime also showed off its nuclear weapons and intercontinental range ballistics, including its new hypersonic missile, reported Seoul-based analysis site NKNews.

Meanwhile, people on social media have been poking fun at a parachutist in a skin-tight blue suit standing among pilots at the exhibition, calling him "Captain North Korea" or "human cannonball."

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