The country’s Academy of Defence Science and the Missile Administration also conducted tests of carbon-fibre bombs and a mobile short-range anti-aircraft missile system, KCNA said.

Kim Jong Sik, a general who oversaw the tests, said the electromagnetic weapon system and carbon-fibre bombs were “special ​assets” for North Korea’s military, KCNA reported.

South Korea’s Joint Chiefs of Staff said on Wednesday that Pyongyang had test-fired multiple missiles over several days.

Analysts also see ​the tests as likely to be a show of force in cutting-edge conventional weapon systems by the nuclear-armed North ⁠for its adversaries and allies.

Chinese Foreign Minister Wang Yi is scheduled to make a two-day visit to North Korea starting on Thursday.

There has also ​been speculation that US President Donald Trump may try to hold a summit with North Korean leader Kim Jong Un on the sidelines of ​his visit to China in mid-May.

Without specifying the number of ballistic missiles launched - a violation of United Nations sanctions - North Korea said it had tested its mobile short-range anti-aircraft missile system as well as the combat capabilities of its tactical ballistic missile warhead.

One test proved the surface-to-surface tactical ballistic missile called Hwasongpho-11 Ka, which is tipped with ​a cluster-bomb warhead, was able to “reduce to ashes any target” covering an area of up to 7 hectares, KCNA said.

Electronic warfare

The tests also follow North ​Korea reiterating its characterisation of South Korea as a “hostile enemy,” dashing recent hopes in Seoul of easing tensions on the Korean Peninsula.

North Korea appears to be upgrading its weapon system ‌with cutting-edge ⁠technology suited for a modern war, said Lim Eul-chul, a professor at Kyungnam University in South Korea.

The electromagnetic weapon system could have the capacity to disable electronic circuits in the enemy’s assets, with the potential ability to cripple South Korea’s F-35A stealth fighter jet or Aegis-equipped destroyers, Lim said.

Carbon-fibre bombs, which have been developed by advanced militaries such as the US and China, are capable of crippling infrastructure like power plants by ​sprinkling conductive strands of carbon fibre ​over a target.

Lim said ⁠they could be a potent weapon in any conflict.

North Korea also said it conducted a firing drill using “low-cost raw materials,” indicating its target for the mass production of weapons, said Yang Moo-jin, a professor at the ​University of North Korean Studies.

The unveiling of such weapons would complicate South Korea’s defence strategy against North ​Korean threats, said ⁠Song Seong-jong, a professor at Daejeon University and a former official at Seoul’s Defence Ministry.

Shin Jong-woo, secretary general of the Korea Defence and Security Forum, said that North Korea was learning lessons from conflicts such as those in Ukraine and the Middle East.

For the first time, he said Pyongyang was also ⁠openly stating ​it was pursuing weapons designed to attack South Korea’s industrial infrastructure.

“North Korea appears to be ​developing these weapons with that asymmetric warfare model very much in mind,” said Shin, noting how it was important to be able to mass-produce weapons and also use electronic ​warfare to disrupt power grids and industrial infrastructure.