Discuss as:

Kim Jong Un inspects North Korean army unit

In a series of undated pictures released by the official Korean Central News Agency on Feb. 21, 2013, North Korean leader Kim Jong Un is shown inspecting Korean People's Army Unit 323, also known as the O Jung Hup-led 7th Regiment, in Pyongyang. 

KCNA via EPA

KCNA - KNS via AFP - Getty Images

KCNA via AFP - Getty Images

KCNA - KNS via AFP - Getty Images

KCNA - KNS via AFP - Getty Images

KCNA - KNS via AFP - Getty Images

KCNA via Reuters

KCNA via Reuters

By David Chance, Reuters

SEOUL, South Korea - North Korea has bolstered its defenses against a "hostile" United States with its third nuclear test, it said on Thursday, noting that countries that had bowed to U.S. pressure to abandon their nuclear plans had suffered "tragic consequences."

Pyongyang carried out its largest nuclear test to date last week, in defiance of U.N. resolutions, prompting warnings of tougher sanctions for the isolated and impoverished state and its young ruler, Kim Jong Un. Read the full story.

The youngest son of Kim Jong Il succeeded his late father in 2011, becoming the third member of his family to rule the unpredictable and reclusive communist state.

Related:

More photos of Kim Jong-Un on PhotoBlog

Glimpses of North Korean life exposed by AP photographer