Expert said to label it 'cruel and unusual punishment' was understatement

A viewing platform can be seen set up nearby

Photographs show six anti-aircraft guns used to shoot line of people

Satellite pictures have revealed Kim Jong-un's regime are using anti-aircraft weapons to brutally execute people, while others watch.

The images, which have been released by the Committee for Human Rights in North Korea (HRNK) and AllSource Analysis, were taken in October last year.

Experts have analysed the photographs which appear to show the Kanggon Military Training Area, close to the capital city Pyongyang, being used as a long-distance firing range.

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Exposed: Satellite images of the Kanggon Military Training Area, where it is believed the executions took place using anti-aircraft guns

They appear to show six ZPU-4 anti-aircraft guns being used to shoot a line of people stood 100 yards away, with a viewing platform located nearby.

Outraged critics said the victims would have been 'pulverised' by the artillery fire, in the latest example of brutality employed by the dictator to suppress his own people.

Greg Scarlatiou, executive director of HRNK, said: 'The most plausible explanation of the scene ... is a gruesome public execution.

'Anyone who has witnessed the damage one single US .50 calibre round does to the human body will shudder just trying to imagine a battery of 24 heavy machine guns being fired at human beings.

'Bodies would be nearly pulverised.

'The gut-wrenching viciousness of such an act would make 'cruel and unusual punishment' sound like a gross understatement.'

Barbaric: North Korean leader Kim Jong-un with a group of training officers of the Korea People's Army in Pyongyang, where the atrocity is thought to have occurred

Evidence: Unusual activity was pictured at the Kanggon Military Training Area in North Korea

Strict regime: North Korean leader Kim Jong-un sits on the front row with a group of training officers of the Korea People's Army in Pyongyang

Kim Jong-un ordered the execution of 15 senior officials this year, including several who complained about the young leader's policies, South Korea's intelligence agency said.

Those executed included two vice minister-level officials, the Yonhap news agency reported, citing legislators who attended a briefing by the National Intelligence Service (NIS).

Both were punished for opposing or complaining about Kim's directives, the legislators said.

It was previously reported that the reclusive leader has used the barbaric tactic before to execute allies of his powerful uncle Jang Song-Thaek.

Jang had played a key role in cementing the leadership of the inexperienced Kim, who took over after the death of his father and long-time ruler Kim Jong-Il in December 2011.

'Pulverized': A ZPU-4 anti-aircraft gun like the on North Korean troops are thought to have used to execute people

Recluse: North Korean leader Kim Jong-un has cancelled a visit to Russia reportedly because the superpower refused to guarantee him special treatment

But analysts said Jang's growing political power and intervention in lucrative trade deals was resented by his young nephew, leading to his execution and those around him.

South Korea's spy agency also expected Kim to travel to Moscow this month to attend an event marking the end of World War Two, the official was quoted as telling the closed-door meeting.

But the trip was cancelled, reportedly because the superpower refused to guarantee him special treatment and over fears he would become a 'freak show for the global press'.

The trip to Russia for its World War II anniversary celebrations in Moscow next week would have been his first overseas visit since taking power after the death of his father, Kim Jong-II, in December 2011.