North Korea fired what are believed to be two short-range ballistic missiles in the country's first weapons test of the year.

South Korean officials reported the projectiles were fired from the coastal town of Wonsan on Monday. They soared 149 miles northeast to a top height of 22 miles before falling into the waters between South Korea and Japan. South Korea's Joint Chiefs of Staff suspect the projectiles were short-range ballistic missiles, and an investigation into the incident is being conducted by South Korean and U.S. officials.

The test was believed to be a test of North Korea’s developing “super-large” multi-rocket launcher, which was tested in 2019. This launcher could give North Korea enough range to strike U.S. bases in Japan or South Korea.

"The repeated firings of ballistic missiles by North Korea is a serious problem for the international community including Japan, and the government will continue to gather and analyze information, and monitor the situation to protect the lives and property of the people," said a Japanese defense minister.

The launch followed a combat-readiness drill that was conducted under the supervision of North Korean leader Kim Jong Un. In photographs of the training session, most of the military leaders were seen wearing face masks, leading some to question whether the country is facing a COVID-19 outbreak.

COVID-19, which is caused by coronavirus, has infected more than 89,000 people globally. While the majority of those infected live in China, where the outbreak started, the second-largest infected population is in South Korea. North Korea has denied that it is facing a coronavirus outbreak, though many doubt the hermit nation’s claim.