Pyongyang may have as many as 20 warheads

The National Assembly Research Service issued a report that said North Korea has at least eight nuclear warheads, and possibly as many as 20, and that it has succeeded in the miniaturization of nuclear warheads.

The research, published on April 14, assesses that North Korean nuclear warheads may weigh 300 kilograms (661 pounds) each, which is lighter than that of Chinese warheads, which weigh around 600 kilograms.

According to the research paper, the United States has conducted more than 1,000 nuclear tests since 1952, and its nuclear warheads weigh 100 kilograms, while Russia has conducted 715 tests since 1955 and possesses warheads weighing 255 kilograms.

The nuclear development of the United States took seven years, while Russia’s took six. Considering this to be the average period required for nuclear development, North Korea, which carried out its first test in 2006, has probably by now finalized the process, the report said. Following its first nuclear test, the North conducted a second test in 2009 and a third in 2013. The latest, its fourth, was carried out on Jan. 6 of this year. As North Korean leader Kim Jong-un ordered the country on March 15 to conduct nuclear and ballistic missile tests, experts and authorities are concerned that Pyongyang may carry out further tests in the near future, possibly a few days before or after the 7th Congress of Workers’ Party of Korea, to be held in early May, the first such meeting in 36 years.

South Korean intelligence sources said earlier this month that North Korea is showing movement toward what could be final preparations for a fifth nuclear test, as they traced an abnormally high volume of movement at its Punggye-ri Nuclear Test site.

Two to three times the number of vehicles, personnel and equipment transfers was spotted at the nuclear test site in Kilju County, North Hamgyong Province, compared to the previous month, Seoul sources said.

Tensions on the Korean Peninsula recently increased as North Korea even stepped up its bellicose rhetoric against Seoul and Washington, which are conducting the largest-ever joint military exercises. The exercises will finish at the end of this month.

The possibility of another intermediate-range missile launch from a mobile launcher has also emerged as the first test ended in failure on April 15, on Kim Il Sung’s birthday.

BY KIM SO-HEE [kim.sohee0905@joongang.co.kr]