Experts have issued a warning to US officials about a terrifying nuclear weapon that they fear North Korea could unleash on the country.
The weapon, known as a nuclear electromagnetic pulse (EMP) bomb, uses high-intensity radio waves emitted from nuclear explosions in the upper atmosphere that scrambles electronics, like a sudden power surge.
The experts claim that such a blast could indirectly wipe out up to 90 per cent of people in the US within a year.
The chilling warning comes from Dr William Graham and Dr Peter Vincent Pry from the EMP Commission, in a new paper titled "North Korea Nuclear EMP Attack: An Existential Threat."
The experts claim that an EMP bomb would be detonated from an altitude of 30-400km above a target, resulting in the loss of electricity to an enormous region, the MailOnline reported.
This could have a range of devastating effects, including knocking out refrigeration for medicines and food, disrupting communication networks, and preventing water processing.
"The result could be to shut down the US electric power grid for an indefinite period, leading to the death within a year of up to 90 per cent of all Americans," the researchers wrote.
"With the development of small nuclear arsenals and long-range missiles by new, radical US adversaries, beginning with North Korea, the threat of a nuclear EMP attack against the US becomes one of the few ways that such a country could inflict devastating damage to the United States.
"It is critical, therefore, that the US national leadership address the EMP threat as a critical and existential issue, and give a high priority to assuring the leadership is engaged and the necessary steps are taken to protect the country from EMP."
According to the experts, North Korea could make an EMP attack against the United States by launching a short-range missile off a freighter or submarine or by lofting a warhead to 30km burst height by balloon.
Alternatively, they say that an EMP attack might be made by a North Korean satellite.
As well as urging officials to prepare for a possible EMP attack, the researchers also warned that North Korea's weaponry is becoming more of an issue.
The experts wrote: "The EMP Commission finds that even primitive, low-yield nuclear weapons are such a significant EMP threat that rogue states, like North Korea, or terrorists may well prefer using a nuclear weapon for EMP attack, instead of destroying a city."
The warning comes just weeks after fears that Kim Jong-Un would unleash an EMP bomb over South Korea in an attempt to disrupt the financial infrastructure.
"Current regulations prohibit the transfer of client information overseas, so we are discussing ways to revise those rules so we can set up data back-up centres abroad," a financial official told the Korea Herald, according to the Sun.
According to the paper, South Korea is also on alert for EMP strikes on its nuclear power stations, government ministries and airlines.
The weapon, known as a nuclear electromagnetic pulse (EMP) bomb, uses high-intensity radio waves emitted from nuclear explosions in the upper atmosphere.
When a nuclear bomb explodes, it emits a burst of gamma rays.
These slam into air molecules, knocking off electrons and accelerating the negatively charged particles.
Earth's magnetic field then sends many of these high-speed electrons towards the planet's poles.
The electrons respond to this by letting off their newly acquired energy as a powerful blast of electromagnetic radiation, including radio waves.
The radio waves can cover an entire continent and cripple circuits inside modern electronics on a vast scale.
This could have a range of devastating effects, including knocking out refrigeration for medicines, disrupting communication networks, and preventing water processing.