South Korea flexes its military muscle in a live fire drill on Friday.

Artillery units carried out the exercise using missiles, rockets and cannon, simulating a combat situation.

The show of military might comes amid heightened tensions on the peninsula after North Korea conducted its third nuclear test on Tuesday despite international warnings.

In North Korea, thousands rally in celebration of the test.

Pyongyang claims the test was an act of self-defence against "U.S. hostility" and threatened stronger steps if necessary.

They've also threatened to attack South Korea if Seoul joins a new round of tightened U.N. sanctions against them.

The test drew international condemnation from around the world, including China, North Korea's only major ally.