North Korea carried out a successful controlled explosion of a test warhead during military exercises held on March 18 and 19, creating an imitation of a nuclear charge, KCNA the official news agency of the country, reported on Monday.

"A launch exercise was conducted to simulate a nuclear strike on the enemy's main facility. The missile was equipped with a test warhead that simulated a nuclear warhead. The tactical ballistic missile was accurately detonated in the East Sea [(Sea of Japan)] at an altitude of 800 meters above the intended target, located 800 km from the launch site. As a result, the reliability of the operation of the nuclear explosion control devices and detonators, which will be installed in the nuclear warhead, has been confirmed once again," the respective statement says.

As per KCNA, the leader of North Korea, Kim Jong-un, stated that the current complex tactical military exercises have significantly improved the effectiveness of the country’s military actions. He also noted that these military exercises are "an important moment for the preparation of nuclear combat forces for the urgent and precise implementation of the important mission of deterring war."

Japan has complained—through its embassy in China—to North Korea regarding the incident.