North Korea fired two short-range projectiles on Monday, the South Korean military said, in the first launches by the regime for more than three months.

The two devices werefired over the sea from the Wonsan area on the east coast, the South’s Joint Chiefs of Staff (JCS) said.

They flew 240km (150 miles) and reached an altitude of 35km before landing in the sea dividing the Korean peninsula and Japan, the JCS added.

Japan’s defence ministry said it has not detected any projectile landing in Japanese territory or its exclusive economic zone, adding that there were no reports of damage to ships or aircraft in the area.

The launches are the first North Korea has conducted since the end of November, according to South Korea’s Yonhap news agency, and come weeks after Pyongyang declared its moratorium on long-range missile tests over.

The North appears to be continuing military drills that the country’s leader, Kim Jong-un oversaw last Friday, JCS said. The exercises are designed to test the combat readiness of units in frontline and eastern areas, North Korea media said.

The JCS could not immediately confirm whether the weapons were ballistic or rocket artillery. “The military is monitoring for additional launches and maintaining readiness,” it said.

The North carried out a series of weapons tests late last year, often describing them as multiple launch rocket systems, although some experts called them ballistic missiles.

It also carried out static engine tests, most recently in December.

At a party meeting at the end of that month, Kim declared that Pyongyang no longer considered itself bound by its moratoriums on nuclear and intercontinental ballistic missile tests, and threatened a demonstration of a “new strategic weapon” soon.

The move came with nuclear negotiations with the US at a standstill and as a unilateral deadline Pyongyang set Washington to offer it fresh concessions on sanctions relief expired.

Analysts said the launches proved that North Korea was determined to continue testing weapons, even as it tries to prevent a coronavirus outbreak that could put intolerable strain on its poor health infrastructure.

“March is pretty reliably missile-testing season for North Korea,” Ankit Panda, senior fellow at the Federation of American Scientists, said in a tweet.

“Looks like Covid-19 hasn’t changed that (or Pyongyang is determined to make it appear as if it hasn’t).”

North Korea has yet to confirm any coronavirus cases, although state media have hinted that an uncertain number of people have been quarantined after showing symptoms.

Seoul and Washington last week said they would postpone forthcoming joint military exercises after South Korea - which has more than 4,000 new cases - declared its highest “severe” alert level over the coronavirus.

Pyongyang has previously fired missiles capable of reaching the entire US mainland and has carried out six nuclear tests, despite being subject to a host of international sanctions.

Kim and Donald Trump ended their second summit, in Vietnam last February, without agreement, prompting the North to end a 17-month pause in ballistic activity and conduct at least 13 rounds of weapons launches last year.