Air forces from South Korea and the US have launched a joint drill codednamed 'Vigilant ACE'.

The drill, which began on Wednesday, brings together more than ten troops from South Korea, and five from the United States.

Various types of fighter jets, early warning aircraft from both sides and some 450 US soldiers stationed at Japan also participating.

The drill aims to test the operational performance of the Korean Air Operations Center, and will last till next Monday.