North Korea fires short-range ballistic missiles after miniaturized warhead claim

SEOUL, March 10 (UPI) -- North Korea fired two short-range ballistic missiles into the sea on Thursday as already marred regional tensions continue to deteriorate.

South Korea's military confirmed the launch, adding the missiles were fired from North Korea's North Hwanghae province. The missiles launched off the east coast flew about 310 miles before falling into the ocean.

After the launch, the North Korean government in Pyongyang said it "nullifies" all inter-Korean cooperative projects and will liquidate South Korean assets in the country, which are within the Kaesong industrial zone.

The launch follows a statement by North Korean leader Kim Jong-un on Wednesday that Pyongyang created a nuclear warhead small enough to fit on a ballistic missile.

A commander of U.S. forces in South Korea told the media in 2014 that he believed North Korea had the ability to miniaturize a nuclear device. In 2015, North Korea publicly announced that it has this capability.

Many analysts outside the country have debated whether North Korea can miniaturize nuclear warheads to be installed on ballistic missiles. If true, this could pose a serious threat to North Korea's neighbors as well as to the United States. South Korea's defense ministry said North Korea had "not yet secured miniaturized nuclear warheads."

North Korea said it tested a nuclear bomb on Jan. 6, and has recently accelerated its belligerent rhetoric in response to recent additional sanctions imposed by the United Nations.

Following the miniaturization claim, U.S. State Department spokesman John Kirby said of Kim Jong-un that "the young man needs to pay more attention to the North Korean people and taking care of them, than in pursuing these sorts of reckless capabilities."