A former child soldier has gone on trial at the prison camp in Guantanamo Bay, the first detainee to face military justice under President Obama, who had promised to close the camp by the beginning of this year. Omar Khadr, a Canadian citizen, was 15 years old when he was captured in Afghanistan. Kim Ghattas reports from Washington.

Jurors at the trial have been told they can consider the age of the defendant when they decide whether he intended to commit a war crime eight years ago in Afghanistan. But the military officers in the jury may not see Omar Khadr's actions as those of a child. In court, they will be face to face with a tall, broad-shouldered, bearded man. The UN has warned the trial may set a dangerous precedent for child soldiers worldwide. No child has been prosecuted for an alleged war crime since World War II. Military prosecutors say Mr Khadr is a clear-eyed al-Qaeda fighter. His lawyers say he is a victim forced into war by his family. Mr Khadr has pleaded not guilty to all five charges against him.