North Korea warned Sunday of a nuclear war if the U.S. and South Korea continued to carry out joint military exercises in the Korean Peninsula. The reaction came in the isolated nation’s official newspaper Rodong Sinmum after the U.S. flew two B-1B Lancer bombers over the North Korean demilitarized zone.

In the commentary, the North said the joint drills by Washington and Seoul would aggravate the situation in the region.

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"A simple misjudgment or a mistake may lead to the outbreak of a nuclear war and that, in turn, is sure to lead to a new world war," Rodong Sinmun’s commentary stated, according to South Korea’s Yonhap News Agency. "The U.S. saying it will regularly deploy strategic bombers to the Korean Peninsula is the same as a crazy act of playing fire on top of an ammunitions locker."

Pyongyang also stated its development of nuclear weapons was justified since the U.S. and South Korea performed military drills.

"U.S. schemes aimed at increasing its threats of nuclear war against the DPRK [Democratic People’s Republic of Korea] for its legitimate and justified measures to defend its sovereignty and dignity will not evade self-destruction," the North Korean newspaper reportedly said.

On Thursday, Washington flew the B-1B Lancer bombers over the East China Sea during a joint mission with Japanese air force, the Pacific Air Forces said in a statement.

“The recent mission demonstrates how the U.S. will continue to exercise the rights of freedom of navigation anywhere international law allows. These actions are consistent with long-standing and well-known U.S. freedom of navigation policies that are applied to military operations around the world,” the statement read.

On Tuesday, North Korea test-launched its first intercontinental ballistic missile (ICBM) named Hwasong-14. The missile reportedly flew over 578 miles and reached an altitude of more than 1,741 miles. After the launch, President Donald Trump criticized the reclusive country its leader on Twitter.

“North Korea has just launched another missile. Does this guy have anything better to do with his life? Hard to believe that South Korea and Japan will put up with this much longer. Perhaps China will put a heavy move on North Korea and end this nonsense once and for all!” Trump tweeted.

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Previously, Pyongyang has issued threats to Washington and Seoul with its ICBM, which is capable of reaching the mainland U.S. It had also threatened the two countries with its nuclear weapons. Last March, the North said it could launch a hydrogen bomb to destroy the Manhattan borough of New York City by securing it on the back of a ballistic missile.

“Our hydrogen bomb is much bigger than the one developed by the Soviet Union,” state-owned news outlet DPRK Today wrote at the time, “If this H-bomb were to be mounted on an inter-continental ballistic missile and fall on Manhattan in New York City, all the people there would be killed immediately, and the city would burn down to ashes.”