Canal Hotel bombing

On the afternoon of 19 August 2003, a suicide bomber drove a truck bomb beneath the office window of Sérgio Vieira de Mello, the United Nations' Special Representative in Iraq, at the Canal Hotel in Baghdad, which housed the United Nations Assistance Mission in Iraq (UNAMI), established only five days earlier. The blast killed 23 people and wounded more than 100, including human rights lawyer and political activist Amin Mekki Medani. The vehicle used was identified as a large 2002 flatbed Kamaz truck, part of the former Iraqi establishment's fleet, and investigators suspected the bomb was built from old munitions, including a single 500-pound aerial bomb from Iraq's pre-war arsenal.

The UN Office for the Coordination of Humanitarian Affairs Humanitarian Information Centre, located directly beneath de Mello's office, suffered a direct hit. Of eight staff and one visitor present, seven were killed instantly; de Mello and Gil Loescher were critically wounded and trapped in the rubble. U.S. Army First Sergeant William von Zehle, later joined by Staff Sergeant Andre Valentine, spent roughly three hours attempting to free the two men without rescue equipment. Loescher survived after his crushed legs were amputated during the rescue; de Mello died before he could be extricated. Marilyn Manuel, a member of de Mello's staff, was initially listed as missing and presumed dead but was found to have survived after being evacuated to an Iraqi hospital that had not notified the UN of her presence.

The attack was followed on 22 September 2003 by a second suicide car bombing near the same UN headquarters, killing the bomber and an Iraqi policeman and wounding 19 others, including UN workers. Together, the two attacks led to the withdrawal within weeks of most of the roughly 600 UN international staff from Iraq, along with employees of other aid agencies; a UN presence under de Mello's replacement, Ashraf Qazi, did not return to Baghdad until August 2004.

In an audiotape published on 6 April 2004, which the CIA assessed as "probably authentic," Abu Musab al-Zarqawi, leader of Jama'at al-Tawhid wal-Jihad, claimed responsibility for the bombing, stating de Mello had been specifically targeted because of his role in East Timor's independence from Indonesian occupation. Other named suspects and claims followed: the Italian newspaper Corriere della Sera identified the suicide bomber as Algerian national Fahdal Nassim; an unknown group calling itself the "Armed Vanguards of the Second Mohammed Army" also claimed responsibility; and in January 2005 a bombmaker for al-Zarqawi's network, Abu Omar al-Kurdi, was captured and said his associates had made the bomb. Awraz Abd Aziz Mahmoud Sa'eed, known as al-Kurdi, was captured by U.S. forces in 2005, confessed to helping plan the attack for al-Zarqawi, was sentenced to death by an Iraqi court, and was executed by hanging on 3 July 2007. In December 2005, Iraqi authorities also issued an arrest warrant for a commander of Ansar al-Sunna in connection with the attack.

UN Secretary-General Kofi Annan condemned the bombing as "unprovoked and murderous violence." In 2008 the UN General Assembly designated 19 August as World Humanitarian Day to honor humanitarian and UN personnel who have lost their lives in the course of their work.