North Korea claimed it had tested a “standardized” nuclear weapon to be mounted on ballistic rockets, during an announcement on Korean Central Television (KCTV) on Friday.

On the same day, an artificial earthquake with a magnitude likely over 5.0 on the Richter Scale was detected near the DPRK’s Punggye-ri testing site. The nuclear test is the second to take place in 2016.

“As the nuclear warhead was standardized, we can now produce a variety of nuclear warheads with high striking power as much as we want and need,” the KCTV announcement said.

The test was conducted to check the power of warhead, the KCTV commentary added, adding that there was no radioactive material leakage.

The North Korean announcement also claimed the nuclear test was a response to the current sanctions regime. The UN Security Council passed additional sanctions in March in response to the DPRK’s fourth nuclear test and satellite launch.

“This test was our countermeasure to the U.S. and our enemies who have sanctioned us, denied our strategic status as the proud nuclear power and have viciously criticized our acts based on our self-defensive rights,” the announcement continued.

The DPRK’s Nuclear Weapons Institute also announced Friday’s test was “for the judgment of the power of a nuclear warhead newly studied and manufactured,” in a statement issued via the Korean Central News Agency (KCNA).

“The nuclear test finally examined and confirmed the structure and specific features of movement of nuclear warhead that has been standardized to be able to be mounted on strategic ballistic rockets of the Hwasong artillery pieces units of the Strategic Force of the Korean People’s Army as well as its performance and power,” it added.

North Korea has previously conducted nuclear tests in 2006, 2009, 2013, and 2016, with explosive yields of less than one kiloton, 2-4 kilotons, 6-9 kilotons, and 7-9 kilotons respectively. The most recent nuclear weapon test may be the most powerful yet.

“(Five) nuclear tests means that North Korea probably now knows a lot about making compact nuclear weapons that can fit on missiles and make efficient use of the country’s stockpile of plutonium and highly enriched uranium … Perhaps the US and South Korea will start taking seriously the idea that North Korea is deploying a nuclear-armed ballistic missile force for use in a conflict,” Jeffrey Lewis at the James Martin Center for Nonproliferation Studies told NK News.

Featured image: KCNA