North Koreans have celebrated another public holiday with familiar routines, laying flowers and bowing in front of statues and portraits of past leaders while the outside world kept a close watch amid speculations that another missile launch– and possibly a nuclear test – is near.

South Korea’s government voiced fears its outlaw neighbour could potentially mark the nation’s 69th founding anniversary with its third test of a developmental intercontinental ballistic missile.

No weapons test had been detected from North Korea as of Saturday afternoon, when people in the capital of Pyongyang went through customary practices of showing loyalty to late leaders Kim Il Sung and Kim Jong Il, the father of third-generation leader Kim Jong Un.

This year’s anniversary celebrations come just after North Korea conducted its sixth and most powerful nuclear test to date last weekend, which it claimed as a detonation of a thermonuclear weapon built for its ICBMs.

The North flight-tested its developmental Hwasong-14 ICBMs twice in July and analysis of flight data suggested that the missiles could reach deep into the US mainland when perfected.

Viewed in the light of Pyongyang’s claim that it had perfected a miniature warhead to be loaded on a long-range missile, US officials have expressed grave fears of an electro-magnetic pulse (EMP) attack that would fry all solid state electronics if a bomb were to be detonated high above the central US.

Experts have warned such an attack would effectively dismantle modern life as the power grid, cars, planes and even domestic electronic devices are rendered effectively inoperable. By one estimate, two-thirds of the US population would perish amid the resulting societal collapse.

Kim Jong-un admires what his state media says is a nuclear warhead capable of striking the US mainland.

The North has a history of marking significant dates with show of military capability, but its recent tests have been seen as driven mainly by technological needs amid an accelerating effort to expand its nuclear weapons arsenal.

“Because we firmly support our respected supreme leader comrade Kim Jong Un, our country will become stronger as a self-reliant, nuclear power, and we will have a great future,” said Pak Kum Hyang, a Pyongyang citizen who came up the city’s Mansu Hill to visit the bronze statues of the late leaders.

“This anniversary of the founding of our country is significant and comes just after we’ve had a successful H-bomb test,” said Choe Sol Ju, another Pyongyang citizen who planned to later go on a family picnic.

North Korea often marks big anniversaries every five years with giant public celebrations. Last year it held a nuclear test on this September anniversary.