The Democratic People's Republic of Korea (DPRK) has fired at least one "unidentified ballistic missile," Seoul's military said Friday.

The DPRK "fires unidentified ballistic missile toward East Sea," Seoul's joint chiefs of staff said, referring to the body of water also known as the Sea of Japan.

Later, Seoul's military said the DPRK fired multiple short-range missiles off South Korea's eastern coastal town of Wonsan.

Meanwhile, Japanese broadcaster NHK, citing government sources, also said the missile "appeared to be short range and has already fallen."

The launch is the latest since the DPRK fired a volley of what Seoul said were short-range ballistic missiles off its east coast on April 22.

Pyongyang said last week it would equip its military with a new 240mm multiple rocket launcher this year, adding that a "significant change" for the army's artillery combat capabilities was underway.

DPRK leader Kim Jong Un inspected a new tactical missile weapons system on Tuesday and called for an "epochal change" in war preparations by achieving arsenal production targets.

The launch also comes a day after advanced South Korean and US stealth fighters, including Washington's F-22 Raptors, staged joint air combat drills, which the DPRK views as rehearsals for invasion.

Inter-Korean relations are at one of their lowest points in years, with Pyongyang declaring South Korea its "principal enemy". It has jettisoned agencies dedicated to reunification and threatened war over "even 0.001 mm" of territorial infringement.

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