North Korea launched two ballistic missiles Wednesday night as part of a tactical nuclear strike drill in response to the deployment of U.S. strategic bombers to the Korean Peninsula during an exercise with South Korea, the country's state media reported.

The official Korean Central News Agency said Thursday a missile unit of the Korean People's Army "fired two tactical ballistic missiles northeastward" and "correctly carried out its nuclear strike mission."

North Korea slammed the U.S.-South Korean exercise as a "serious threat" and tantamount to plans for a pre-emptive nuclear strike by the United States, according to KCNA.

The projectile launches came after U.S. B-1B bombers were deployed to the region for a joint exercise with South Korean forces on Wednesday as part of the countries' annual Ulchi Freedom Shield large-scale military exercise from Aug. 21.

KCNA also reported that North Korean leader Kim Jong Un visited the training command post of the General Staff of the Korean People's Army on Tuesday and observed a command drill involving the whole army.

The drill was "aimed at occupying the whole territory of the southern half by repelling the enemy's sudden armed invasion and switching over to an all-out counterattack," KCNA reported.

North Korea has criticized joint U.S.-South Korea military exercises as rehearsals for invasion.

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