News: North Korea leader touts thrilling sound of H bomb in test order

North Korean leader Kim Jong-Un personally signed the order three weeks ago authorising Pyongyang's latest nuclear test, calling for 2016 to kick off with the "thrilling sound" of a hydrogen bomb explosion.

The North said Wednesday it had conducted its first "successful" miniaturised hydrogen bomb test. The news was broadcast on state television, which also showed a copy of Kim's initial signed order dated December 15.

The television also showed a second order dated January 3 in which Kim signed off his final approval for the test to be conducted on January 6. Kim, who took over after the death of his father Kim Jong-Il in December 2011, also presided over the country's third nuclear test in February 2013.

A hydrogen, or thermonuclear, bomb uses fusion in a chain reaction that results in a far more powerful explosion than the fission blast generated by uranium or plutonium alone. North Korea was believed to be years from developing such a sophisticated device, and experts voiced scepticism that Wednesday's test was indeed of a hydrogen bomb.