US citizen detained in North Korea, embassy officials claim

The former US-Korean professor was arrested at Pyongyang International Airport on Friday, where he stayed for almost a month to work on humanitarian activities, the Yonhap news agency reported.

The reported arrest is the latest American to be detained in the isolated country. Last year, Otto Warmbier, then a 21-year-old University of Virginia student from suburban Cincinnati, was sentenced to 15 years of hard labor in prison after he confessed to trying to steal a propaganda banner.

In April 2016, Dong-chul, a 62-year-old naturalised USA citizen born in South Korea was sentenced to 10 years' hard labour for espionage. United States vice-president Mike Pence said on Saturday it would arrive "within days" but gave no other details.

This would come just as the country plans to celebrate another major holiday on Tuesday - the 85th anniversary of the founding of the Korean People's Army, an occasion they normally use to show off military advances.

However, in photos dating from Wednesday, the analysts noted that North Korea appears to be preparing for what would be its sixth nuclear test.

It has in the past marked important anniversaries with tests of its weapons.

North Korea has pushed the world to the brink of World War 3 with a series of nuclear weapon and ballistic missile tests. It has also threatened to lay waste to South Korea and Japan.

Japan's show of naval force reflects growing concern that North Korea could strike it with nuclear or chemical warheads.

North Korean media responded by warning of an unspecified "super-mighty pre-emptive strike".

This message, which was one of three delivered Saturday, echoed the message delivered by a top official at the massive "Day of the Sun" military parade in Pyongyang earlier this month.

He was on his way out of the country, sources have said.

The US aircraft carrier USS Carl Vinson transits the Sunda Strait, Indonesia on April 15, 2017.

The latest detention comes amid high tension on the peninsula, with the United States warning its "strategic patience" on the North's nuclear programme is over.

South Korea has put is forces on heightened alert. YUST, a university in neighbouring China, has a sister university in Pyongyang.

Last week, President Donald Trump suggested it was steaming towards North Korea - when it was in fact heading to Australia.