Veil of secrecy surrounds North Korea party congress

The youngest son of North Korean leader Kim Jong-il has been appointed to two key party posts, in a move widely seen as part of a gradual transfer of power.

Kim Jong-un was named vice-chairman of the Central Military Commission of the Workers' Party and was appointed to its central committee, state media said.

Kim Jong-il, thought to be in poor health, was re-elected as leader at the party's first congress for 30 years.

But as John Simpson reports from neighbouring South Korea, events in Pyongyang have been shrouded in secrecy.