BBC News with Iain Purdon

New mobile phone video has emerged from Libya of the moments leading up to the death of Muammar Gaddafi. The United Nations high

commissioner

for human rights has said there should be a full investigation into how Colonel Gaddafi was killed. Gabriel Gatehouse reports from Misrata.

Today new

footage

emerged of Colonel Gaddafi's final moments. He's seen being

led away

on foot by rebel fighters who quickly surround him. Guns are pointed at his head, and voices can be heard arguing over whether to kill him. This footage appears to have been filmed later. He's still alive, and he's been lifted onto a truck. Some time after that, he's filmed lying on the ground where he appears lifeless. Several hours later, he was pronounced dead. No one knows who fired the shot that killed him.

Contrary to Islamic tradition, his body is yet to be buried and lies in a cold storage room in Misrata. The body of one of Colonel Gaddafi's sons, Mutassim, is also in cold storage and has been on display. It has two gunshot wounds - one in the neck and one in the chest. Another son Saif al-Islam, who was widely considered to be the heir to Colonel Gaddafi, is thought to have fled Sirte as NTC fighters took control of the town. Some members of the

interim

authorities said he'd been wounded and captured by revolutionary fighters, but there's been no independent evidence of this.

President Obama has confirmed that United States forces will complete their