GENEVA (AFP) - Activists stood in silent protest as the United States on Thursday defended its record before a UN anti-torture watchdog, raising their fists and displaying pictures of victims of police brutality.

On the second and final day of the UN Committee Against Torture's review of the United States, a group of young protesters flaunted UN protocol and stood up as the US delegation began discussing the issue of abuse by police.

Around 10 youths with the Chicago-based group We Charge Genocide (WCG) wearing matching T-shirts and brandishing pictures of Dominique Franklin - a 23-year-old who died in June after police used a taser on him while he was handcuffed - rose silently, their fists held in the air.

Soon members of other non-governmental organisations in the room followed suit, forcing the delegation of some 30 high-level US officials to continue their responses to committee questions with a sprinkling of fists throughout the room.

The parents of 18-year-old Michael Brown, who was shot and killed by a white police officer in Ferguson, Missouri last August, sat silently watching on, but did not join in.

At its first review of the United States since 2006 and the first since President Barack Obama came to power, the committee had on Wednesday grilled the delegation on a range of issues ranging from torture at Central Intelligence Agency "black sites", to continued detention at the US military prison at Guantanamo Bay in Cuba, prisoner abuse, and detention of illegal immigrants.

The committee, tasked with reviewing the records of the 156 countries that have ratified the Convention Against Torture, also took the delegates to task over excessive use of force by law enforcement officers, including the militarisation of local police forces and widespread and sometimes lethal use of tasers.

While acknowledging a range of past abuses during the so-called "War on Terror" under the previous administration of George W. Bush, the delegates stressed that Washington had made great strides to right those wrongs.

"We believe that torture and cruel, inhuman and degrading treatment and punishment are forbidden in all places, at all times, with no exceptions," said Tom Malinowski, Assistant Secretary at the US Bureau of Democracy, Human Rights and Labour.

When the delegation turned its attention to the questions on police brutality, insisting that the US judicial system ensured that abusive officers could be held accountable and prosecuted, the members of WCG stood up.