In May 2009 the Sri Lankan army finally crushed the Tamil Tiger rebels, ending 25 years of civil war.

In the final weeks of the conflict thousands of civilians were trapped alongside the rebel fighters under heavy shelling as the government forces closed in.

Foreign journalists and aid workers were prevented from reaching the fighting.

Witness History speaks to the former United Nations official Gordon Weiss, who looked on helplessly from the Sri Lankan capital as the final days of the war unfolded.

Witness: The stories of our times told by the people who were there.