Celebrations erupted across Juba as jubilant crowds marked South Sudan's long-awaited day of freedom on Saturday, when the chronically underdeveloped region became the world's newest nation."Today we shall raise the flag of South Sudan to join the nations of the world," said Pagan Amum, the secretary general of the ruling Sudan People's Liberation Movement, speaking at the base of a giant flagpole.

Pakistan has warned its cooperation in the US-led war on al-Qaeda was at risk after heavily criticising the top US military officer for suggesting it could have approved a journalist's murder. The row threatened to further strain relations already damaged by a covert US raid that killed Osama bin Laden two months ago and is the latest sign that cooperation in the war on al-Qaeda and in neighbouring Afghanistan is at risk.