SEOUL - New stamps featuring North Korea's founder Kim Il Sung, former leader Kim Jong Il and current leader Kim Jong Un - the grandson and son of the two late leaders - were released in celebration of the 70th anniversary of the founding of Mangyongdae Revolutionary School.

Kim Jong Un recently visited the Red Flag Mangyongdae Revolutionary School, an elite military educational establishment in Pyongyang, capital of North Korea, UPI on Friday (Oct 13) cited South Korean network KBS as reporting.

"Comrade Kim Jong Un visited the Mangyongdae Revolutionary School to celebrate the 70th anniversary of its founding," Pyongyang's state-controlled KCTV reported, showing footage of his visit on Friday.

The school, which was originally opened to house and educate children of soldiers killed in battles, has been providing all-round education with a strong military emphasis as many of the pupils are expected to go on to senior careers in the military, according to an Associated Press report.

Tensions over North Korea's nuclear weapons programmes have soared in recent months, with Pyongyang launching a flurry of missiles and conducting its sixth and most powerful nuclear test last month in defiance of international sanctions.

US President Donald Trump's continued threats of military action against Pyongyang to tame its weapons ambitions have fuelled fears of conflict on the Korean peninsula and next week the United States and South Korea will begin a major naval drill as a show of force against the North.

North Korea is believed to be preparing to launch a ballistic missile ahead of the joint naval drill by the US and South Korea, the Donga Ilbo daily reported on Saturday (Oct 14), quoting a government source.

Satellite pictures show ballistic missiles mounted on launchers being transported out of hangars near Pyongyang and in the North Phyongan province, the newspaper said, adding that US and South Korean military officials suspect the North might be preparing to launch missiles capable of reaching US territory.