North Korea fired another unidentified projectile on Sunday (Sept. 20) afternoon, just three hours after launching a short-range ballistic missile (SRBM) toward the East Sea.

South Korea's Joint Chiefs of Staff (JCS) announced at around 6 p.m. today that North Korea fired an unidentified projectile into the East Sea.

The JCS is analyzing the specifications and flight range of the projectile.

Earlier, at around 3 p.m. today, North Korea fired a single short-range ballistic missile from the Wonsan area toward the East Sea.

That missile flew approximately 450 kilometers and is presumed to belong to the Hwasong-11 series, one of North Korea's flagship SRBM types.

If the newly launched projectile is confirmed to be a ballistic missile, it would mean North Korea launched ballistic missiles twice within a three-hour span.

In a statement by Kim Yo-jong, director of the General Affairs Department of the Workers' Party of Korea, released on Sept. 18, North Korea had threatened that "responsive actions with proportionality or an offensive nature surpassing it" were necessary, protesting against recent U.S.-led multinational naval drills such as Pacific Vanguard.

The launch of ballistic missiles just two days later is seen as putting those "responsive actions" into actual practice.