South Korea’s defence ministry condemned the murder as a “brutal act”. Seoul said the man disappeared from a patrol boat near the border. He worked for the fisheries department and was later found in the North’s waters.
The ministry said North Korean soldiers shot him, poured oil over his body and set him alight.
It is believed that the move was an anti-coronavirus measure.
Pyongyang has not yet commented on the issue.
It would mark the second time Northern troops have shot and killed a Southern civilian, following the death of a tourist at the hands of a soldier at Mount Kumgang in 2008.
Should Pyongyang confirm that its soldiers carried out the killing, the South’s allies, like the US, could respond heavy handedly.
On becoming president in 2016, Donald Trump stuck to his predecessor’s position: that the North’s nuclear programme is unacceptable and that Pyongyang has to give up all its nuclear weapons.
According to military affairs and national security expert, Yochi Dreazen, in his 2018 Vox report, the US has a clear goal in which it would deal with North Korea if the country were to enter a war alongside South Korea.
He explained: “If the US and South Korea went to war with the North, their key strategic goal would be to capture or destroy all of Pyongyang’s nuclear sites, as well as the bases that house its long-range missiles.”
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The North has been building its arsenal of nuclear weapons for years.
It is thought to have around 30 to 40 nuclear warheads, with production sufficient enough to develop six or seven nuclear weapons every year.
The country also claims to have developed a hydrogen bomb and to be able to mount it on a missile.
Studies suggested that the Hwasong-14 had the most lethal potential – estimating it could travel as far as 10,000km if fired on a maximum trajectory.
This would have given Pyongyang its first intercontinental missile (ICBM), capable of reaching New York.
Eventually, Hwasong-14 only reached a peak altitude of 3,000km, though its successor, Hwasong-15, managed an altitude of 4,500km.
Hwasong-12 missiles, tested in 2017, achieved the desired result and could travel as far as 4,500km (2,800miles) – putting US military bases on the Pacific island of Guam within striking distance.
Guam is home to more than 163,000 American citizens.
Also within distance is Japan, which has a sizable US military presence.