A US military base near South Korea’s border with the North accidentally blasted an alert siren instead of a bugle call as soldiers monitored the rogue state.

Human error has been blamed for the accidental alarm at Camp Casey.

The operator immediately identified a mistake had been made and informed all units that it was a false alarm, Lieutenant Colonel Martyn Crighton, a public affairs officer, told the Associated Press news agency.

He added that no operations had been affected as a result of the incident on Thursday evening.

It came just a day before Japanese broadcaster NHK caused panic by mistakenly posting a news alert saying North Korea had fired a missile over Japan which had landed in the sea off the island of Hokkaido.

The broadcaster apologised, saying the alert was for media training purposes.

Kim Jong-un: Power in pictures Show all 20 1 /20 Kim Jong-un: Power in pictures Kim Jong-un: Power in pictures Kim Jong-un rides a horse during snowfall in Mount Paektu in this image released by North Korea's Korean Central News Agency on 16 October 2019 Reuters Kim Jong-un: Power in pictures Kim Jong-un visits the newly built Pyongyang Orphans' Primary School on 2 February 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects a women's company under Unit 5492 of the Korean People's Army in November 2019 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects the test-fire of intercontinental ballistic missile Hwasong-14 at an undisclosed location in July 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un celebrates the successful test-fire of the intercontinental ballistic missile Hwasong-14 at an undisclosed location in July 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects a potato at the Samjiyon Potato Factory in North Korea in October 2018 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un rides a horse through a forest in this image released by North Korea's Korean Central News Agency on 16 October 2019 EPA Kim Jong-un: Power in pictures Kim Jong-un inspects a block of frozen fish at a processing facility in North Korea in November 2018 Reuters Kim Jong-un: Power in pictures Kim Jong-un celebrates the succeful launch of a strategic submarine-launched ballistic missile in August 2016 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un shakes hands with Donald Trump as they meet for the first time at the Capella Hotel on Sentosa island in Singapore in June 2018 Reuters Kim Jong-un: Power in pictures Kim Jong-un and Donald Trump share a glance as they meet in the Demilitarised Zone in Panmunjon, Korea in June 2019 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects mushrooms at Pyongyang Mushroom Farm AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects a super-large multiple rocket launcher ahead of a test in September 2019 Reuters Kim Jong-un: Power in pictures Kim Jong-un inspects an apple farm in South Hwanghae Province in September 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects an apple farm in South Hwanghae Province in September 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects dental wares at a newly built factory in June 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un visits Farm No 1116 in September 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un visits a motor factory in November 2017 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un rides a horse during snowfall in Mount Paektu in this image released by North Korea's Korean Central News Agency on 16 October 2019 AFP/Getty Kim Jong-un: Power in pictures Kim Jong-un inspects the Command of the Strategic Force of the Korean People's Army at an undisclosed location in August 2017 AFP/Getty

Both incidents come at a time of heightened tension in the region after North Korea set an end-of-year deadline for the US to offer mutually acceptable terms for a stalling nuclear deal between the two countries.

Kim Jong-un had previously said he was planning a “Christmas gift” for Donald Trump – widely interpreted to mean he was plotting new ballistic missile tests over the festive period – although Mr Trump himself appeared sanguine about the threat.

“Maybe it's a nice present,” he said at an armed forces rally. “Maybe it's a present where he sends me a beautiful vase as opposed to a missile test. I may get a vase. I may get a nice present from him. You never know."

Pyongyang has largely held off such tests since three meetings between the two leaders including a brief one at the border of North and South Korea in June this year.