North Korea launched 30 short-range rockets into waters off its east coast early Saturday, South Korea's military said, in what appeared to be its latest show of force against Seoul and Washington.

North Korea fired three bursts of rockets between 4 a.m. and 6:10 a.m. from a coastal area near Wonsan, according to the Joint Chiefs of Staff.

It said the projectiles appeared to be FROG surface-to-surface rockets, noting that they are estimated to have flown around 60 kilometers.

The North did not impose flight or navigation bans over the waters where the rockets landed, according to the Joint Chiefs of Staff.

The North has launched a barrage of short-range missiles and rockets into waters off its east coast in recent weeks in apparent protest at ongoing South Korea-U.S. joint military drills.

The North has denounced the joint drills as a rehearsal for invasion, while Seoul and Washington have said they are defensive in nature.

The latest launch came a week after North Korea threatened to bolster its nuclear deterrence and further demonstrate its military might as long as nuclear threats and blackmailing by the United States persist.

North Korea claims its nuclear programs are a deterrent against alleged U.S. hostility.

The North's recent threats have been widely seen as an indication that it may carry out a fourth nuclear test or launch a long-range rocket.

North Korea conducted nuclear tests in 2006, 2009 and February 2013, drawing international condemnation and U.N. sanctions.

(Yonhap)