North Korea said on Sunday that it fired a Hwasong-15 intercontinental ballistic missile (ICBM) the previous day in a "sudden launching drill."

The North's official Korean Central News Agency (KCNA) said that the North carried out the high-angle launch of the missile on Saturday afternoon at an international airfield in Pyongyang, with the guidance of the Missile General Bureau.

The KCNA said the missile flew 989 kilometers for four-thousand-15 seconds up to a maximum altitude of five-thousand-768 kilometers before hitting a pre-set area in the open waters of the East Sea.

The KCNA said that the drill was suddenly organized without previous notice under an emergency firepower combat standby order given at dawn on Saturday, followed by a written order by North Korean leader Kim Jong-un.

The sudden drill was reportedly aimed at verifying the reliability of the weapons system and enhancing the combat readiness of the country's nuclear force.