The North Korean military is reportedly setting up special military units which carry "nuclear backpacks". Top performing North Korean soldiers are claimed to be handpicked from several military divisions to form the special battalion-sized units.

A North Korean source, who knows about the developments, told Radio Free Asia (RFA): "Outstanding soldiers were selected from each reconnaissance platoon and light infantry brigade to form the nuclear pack unit the size of a battalion."

Pyongyang is thought to have been building this division since March 2016. It is close to impossible to independently verify any of this information in the highly isolated and secretive country.

The soldiers selected for this particular division are claimed to have been given the same uniforms and other facilities except for backpacks. They are currently trained with mock nuclear packs, weighing anywhere between 10 and 28 kgs. In the past, some North Korean soldiers were seen wearing backpacks with radiation symbols during their annual military parades.

The anonymous source was cited as saying that "the enemy's aircraft carriers will capsize even if a nuclear backpack is detonated at a distance. This is aimed at reinforcing the psychological armament of North Korean soldiers and to prevent them from being afraid of war".

The country's top military officials have reportedly informed the soldiers that detonation of the backpacks would not generate massive nuclear explosions but spray radioactive material on enemy forces.

"Once the uranium has been sprayed [in an area], people cannot live there for several decades because of radioactive contamination. I don't understand why they are making those weapons," a nuclear engineer was quoted as telling the North Korean source by the RFA.

Tensions have escalated in the Korean peninsula after the North launched a ballistic missile from a submarine on 24 August. Following the test-firing, the country's leader Kim Jong-un not only hailed the event as successful but also hastened the mounting of nuclear warheads on ballistic missiles.