"We confirm that North Korea has launched one missile from Wonsan airbase this morning (KST) and failed," a South Korean military official told NBC News. "We are in the process of analyzing the type of the missile. South Korea's military is fully prepared for the possibility of North Korea's additional missile launch."

North Korea attempted to conduct a missile launch on Wednesday, but the South Korean military says it failed.

American officials also confirmed the unsuccessful attempt.

"U.S. Pacific Command detected what we assess was a failed North Korean missile launch attempt... in the vicinity of Kalma," Commander Dave Benham said in a statement, referring to an area in the North Korean city of Wonsan.

"A missile appears to have exploded within seconds of launch," Benham added.

Japan first detected the launch earlier on Wednesday, with government sources initially telling Kyodo News that Pyongyang may have launched several missiles.

Wednesday's incident is the latest sign of escalated aggression from North Korean supreme leader Kim Jong-un. Earlier this month, his government fired four ballistic missiles after testing a new type of missile known as the Pukguksong-2 in early February.

Strategists say Kim is testing President Donald Trump, who has signaled a tough stance on the nation. During a recent Asia tour, Secretary of State Rex Tillerson acknowledged that two decades of American efforts to denuclearize North Korea had not succeeded and highlighted the need for a fresh policy approach.

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