New York, Aug 19 (DPA) The UN Wednesday marked the first World Humanitarian Day to pay tribute to humanitarian workers killed in missions, including the 22 UN staffers who died in a Baghdad attack six years ago.

Among those killed in Baghdad Aug 19, 2003 was Sergio Vieira de Mello, the Brazilian chief of the UN mission in Iraq, which was freshly set up following the US invasion of Iraq to oust Iraqi dictator Saddam Hussein.

The UN mission in Iraq, located then at the Canal Hotel in Baghdad, was blown up by a massive bomb while it was fully staffed.

In another recent attack,the UN office in Algiers was bombed in December 2007, killing 17 local and foreign staffers.