The North Korea's Academy of Defense Science and the Missile Administration also conducted tests of carbon-fiber bombs and a mobile short-range anti-aircraft missile system, KCNA reported.
Kim Jong Sik, a general who oversaw the tests, said the electromagnetic weapon system and carbon-fiber bombs were "special assets" for North Korea's military.
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, according to Reuters.
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.