The action comes as analysts ponder how deeply the secretive country has been affected by the coronavirus.
North Korea on Saturday fired two short-range ballistic missiles into the sea, South Korea’s military said.
The development came as Pyongyang continues to expand military capabilities amid deadlocked nuclear negotiations with the Trump administration and a crippling global health crisis surrounding the coronavirus.
South Korea’s Joint Chiefs of Staff said the projectiles were fired around 6:45 and 6:50am local time from an area around the county of Sonchon in western North Korea.
They flew 255 miles cross-country before landing in waters off the eastern coast.
South Korea and the US are analysing the launches. Seoul’s military urged the North to immediately stop its “very inappropriate” military demonstrations when the world is struggling to cope with coronavirus.
Japan’s Defence Ministry said the projectiles did not reach Japanese territory or its exclusive economic zone.
The North conducted two previous rounds of similar short-range launches and other military exercises this month after leader Kim Jong Un entered the new year vowing to bolster his nuclear deterrent in face of “gangster-like” US sanctions and pressure.
While the North is clearly determined to advance its missile capabilities, Japan’s Defence Minister Taro Kono said Pyongyang’s demonstrations could also be aimed at “bracing the regime together” amid the coronavirus crisis.
It was not immediately clear what North Korea tested.
Flight data released by the South Korean and Japanese militaries suggests the North could have tested one of its new mobile, solid-fuel missile systems it first demonstrated last year.
Military analysts say such weapons, designed to overwhelm missile defence systems with their manoeuvrability and low-altitude flights, potentially strengthen the North’s ability to strike targets in South Korea and Japan, including US bases there.
North Korea in recent months has also demonstrated what it described as a “super large” multiple rocket launcher, which experts say was likely tested earlier this month.
North Korea’s state media earlier reported Mr Kim had supervised an artillery firing competition between army units in the country’s west on Friday.
The KCNA said Mr Kim expressed satisfaction over the exercise that was aimed at evaluating combat readiness. The report did not mention any direct comments by Mr Kim towards Washington or Seoul.
Pyongyang’s official Korean Central News Agency also said on Saturday the North had decided to hold a session of its rubber-stamp parliament on April 10. It was not immediately clear what would be discussed.
Nuclear talks have been locked in a stalemate since the collapse of the second summit between Mr Kim and President Donald Trump in early 2019, when the US rejected North Korean demands for major sanctions relief in exchange for a partial surrender of its nuclear capabilities.
Following the breakdown in talks, the North ended a 17-month pause in ballistic activity and conducted at least 13 rounds of weapons launches last year while pressuring Washington and Seoul for concessions. Those weapons also included a developmental mid-range missile that could be launched from submarines.
Some experts say the lull in North Korean launches between November and March could have been caused by the coronavirus pandemic, which started in mainland China in December.
Mr Kim has vowed to build up his nuclear arsenal and achieve a “frontal breakthrough” against sanctions while urging his nation to stay resilient in a struggle for economic “self-reliance”.
But some experts say North Korea’s self-imposed lockdown amid the coronavirus crisis could potentially hamper his ability to mobilise people for labour.
North Korea has not publicly confirmed a single case of the COVID-19 illness, but state media have described anti-virus efforts as a matter of “national existence”.
Experts say an epidemic in North Korea could have dire consequences due to the country’s poor health system and shortage of medical supplies.
The country has banned foreign tourists, shut down nearly all cross-border traffic with China, intensified screening at entry points and mobilised health workers to monitor residents and isolate those with symptoms.
*** Olivia Isibor