Fears are growing that North Korea could launch more missiles after Pyongyang called joint US-South Korea military exercises an "open provocation and dangerous war drill".
The communist state said it would respond to the exercises with "sustained, resolute and overwhelming practical military measures" and lambasted the joint action as “military confrontation hysteria”.
The warning comes amid a flurry of missile tests by North Korea, with the latest ballistic missiles launched on Saturday, just days after the US and South Korea wrapped up their largest-ever air force drills.
Rockets flew approximately 130 kilometres toward the country’s western sea.
The General Staff of its Korean People's Army said in a statement reported by the official KCNA news agency that the 'Vigilant Storm' exercises were an "open provocation aimed at intentionally escalating the tension" and were war drills "of very high aggressive nature towards North Korea".
Pyongyang said it would respond with the “toughest counteraction” to any attempts by “hostile forces” to infringe on its sovereignty or security interests, the Associated Press reported.
Some experts believe that Pyongyang's anxiety over the drills is because its air force is one of the weakest branches of its military, void of modern jets and properly trained pilots.
Tensions remain high following the US Department of Defense warning to North Korea on Thursday that if Pyongyang used any nuclear weapon against Seoul or other regional allies, the US would destroy Kim Jong-un's regime.
"Any nuclear attack against the United States or its Allies and partners, including the use of non-strategic nuclear weapons, is unacceptable and will result in the end of the Kim regime," said Defense Secretary Lloyd Austin in a statement.
Then, on Friday, South Korea scrambled 80 fighter jets after more than 100 North Korean aircraft were detected near the disputed border between the two countries.
The US confirmed earlier this week that its military exercise with the South would be extended to Saturday November 5 despite being due to conclude on Friday.
"Our combined air exercise with the ROK has currently been extended to November 5," the Pentagon said in a statement.
"We remain in close coordination with our ROK ally on any additional changes and the security environment on the Korean Peninsula. Our commitment to the defense of the ROK is ironclad."
The US has also called for a public United Nations Security Council meeting on Friday and accused Russia and China of providing "blanket protection" to North Korea from further Security Council sanctions.
In May, China and Russia vetoed a US attempt to slap North Korea with more UN sanctions.
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