North Korean dictator Kim Jong Un removed his top military leader last week during an annual end-of-year meeting with the nation's highest officials.
Pak Jong Chon, vice chairman of the Central Military Commission, was the second most powerful military official in the country, behind only Kim himself. He was replaced by one Ri Yong Gil during a series of meetings with the Commission and Kim's Central Committee.
Pak was seen seated with other commission members early on in a meeting last week, but his seat then went unoccupied. He was also not present in official photos Kim's regime released from the event, according to Reuters.
The leadership shakeup comes as Kim is growing increasingly aggressive with ballistic missile tests, having launched dozens throughout last year.
The U.S., South Korea and Japan have all ramped up military activity in the region as a result, leading to more aggressive language coming out of Pyongyang. The country focused heavily on Japan's recently announced plan to bolster its military spending.
"Japan's foolish attempt to satiate its black-hearted greed – the building up of its military invasion capability with the pretext of a legitimate exercise of self-defense rights – cannot be justified and tolerated," a foreign ministry spokesman told state media in December.
North Korea has long attacked Japan for the atrocities it committed throughout Asia prior to and during the world wars. The country now argues Japan seeks a return to its colonial ambitions through its alliance with the U.S.
Japan's renewed emphasis on its military is focused on not only North Korea but China as well. China also has grown increasingly aggressive toward Taiwan and has refused to acknowledge its lack of sovereignty in areas of the South China Sea.
The U.S. and its allies in the region have sought to prepare Taiwan for a potential invasion, with some threatening potential military intervention.
At least one of North Korea's ballistic missiles flew over the island of Japan, and China conducted weeks of military exercises last year in an apparent trial run for invading Taiwan.