North Korea has fired at least one "unidentified projectile" towards the sea of Japan on Thursday, read a statement from South Korea's Joint Chiefs of Staff (JSC).

"North Korea fired two unidentified projectiles toward the East Sea (the Sea of Japan)," the JSC statement read.

JSC said the "projectiles were fired from areas in South Pyongan Province in the afternoon," adding that, "Our military is monitoring the situation in case of additional launches and maintaining a readiness posture."

No details were given on the projectiles' type and or flight range.

The Japan Coast Guard has requested all vessels operating in the Sea of Japan to remain alert and monitor news channels.