North Korea said Tuesday that it conducted the test-firing of a tactical guided missile a day earlier to confirm the accuracy of the weapons system under production.

On Monday, South Korea's military said the North fired two suspected short-range ballistic missiles eastward from the Sunan airfield in Pyongyang, marking its fourth show of force this month.

"The test-fire was aimed to selectively evaluate tactical guided missiles being produced and deployed and to verify the accuracy of the weapon system," the North's official Korean Central News Agency (KCNA) said.

North Korean leader Kim Jong-un did not attend the firing.

Monday's firing appears to have involved the North's version of the US' Army Tactical Missile System (ATACMS), called the KN-24, according to a photo released by state media. The missile is known to fly on a complicated trajectory to evade interception.

"The two tactical guided missiles launched in the western area of the DPRK precisely hit an island target in the East Sea of Korea," the KCNA said. DPRK stands for the North's official name, the Democratic People's Republic of Korea.

The Academy of Defense Science which conducted the test-fire "confirmed the accuracy, security and efficiency of the operation of the weapon system under production," it added.

The North's latest saber-rattling came just three days after it fired two missiles from a train-based platform Friday, hours after Pyongyang warned of a "stronger and certain reaction" to new US sanctions.

The United States announced fresh sanctions on six North Koreans involved in the regime's weapons of mass destruction and ballistic missile programs on Wednesday following the North's consecutive launch of what it claims to be a hypersonic missile on Jan. 5 and 11.

Nuclear negotiations between Washington and Pyongyang have remain stalled since the Hanoi summit in February 2019.

The latest missiles flew about 380 kilometers at an altitude of 42 km within a four-minute interval, according to the South's Joint Chiefs of Staff. (Yonhap)