Navi Pillay, U.N. High Commissioner for Human Rights, said that the al Qaeda leader, killed in a U.S. operation in Pakistan on Sunday, was a "very dangerous man" who had claimed "command responsibility for the most appalling acts of terrorism", including the Sept. 11 attacks on America nearly a decade ago.

"This was a complex operation and it would be helpful if we knew the precise facts surrounding his killing. The United Nations has consistently emphasised that all counter-terrorism acts must respect international law," she said in a statement issued in response to a Reuters request.

US President Barack Obama gets precious few opportunities to announce a victory. So it's no wonder he chose grand words on Sunday night as the TV crews' spotlights shone upon him and he informed the nation about the deadly strike against Osama bin Laden. "Justice has been done," he said.

It may be that this sentence comes back to haunt him in the years to come. What is just about killing a feared terrorist in his home in the middle of Pakistan? For the families of the victims of the 9/11 attacks, and for patriotic Americans who saw their grand nation challenged by a band of criminals, the answer might be simple. But international law experts, who have been grappling with the question of the legal status of the US-led war on terror for years, find Obama's pithy words on Sunday night more problematic.
Claus Kress, an international law professor at the University of Cologne, argues that achieving retributive justice for crimes, difficult as that may be, is "not achieved through summary executions, but through a punishment that is meted out at the end of a trial."