Abu Musab Al Zarqawi was best known as a notorious member of the Iraqi insurgency and as leader of the country's Al Qaida network.
Jordanian born Zarqawi's left school at the age of 17, when personal accounts described him as a simple, violently tempered and barely literate gangster.
Jordanian intelligence reports suggest that Zarqawi was jailed briefly in the 1980s.
In 1989 Zarqawi rose to prominence as an 'Afghan Arab'. Like Osama Bin Laden, he led foreign fighters against Soviet forces in Afghanistan.
It was during this time that reports suggest he developed a radical Islamist agenda, becoming a writer for an Islamist newsletter.
On his return to Jordan, Zarqawi was jailed for plotting to overthrow the monarchy and establish an Islamic regime.
He fled Jordan following his release but was sentenced to death in his absence for plotting to kill American and Israeli tourists.
In 2002 Zarqawi was blamed for the assassination of an American aid official in Amman. The following year he was named as the organizer of a series of bombings in Morocco and Turkey.
He first surfaced in Iraq as the leader of Tawhis, the Jihad insurgency group. In 2004 the two merged and Zarqawi became leader of the Al Qaida network in Iraq.
In Iraq, his primary motive was to target Shias. In a letter released by the Americans in 2004, Zarqawi spoke out for sectarian conflict in the country as a means of undermining America's presence. He is thought to be responsible for the bomb attacks on recruitment centres for Iraqi security forces that killed nearly 100 people.
The beheadings of foreign hostages by the Tawhid and Jihad group remain among his most memorable crimes, sending shockwaves around the world.
After several attempts on his life by the US in 2005, a $25m bounty was put on his head, the same amount as Osama Bin Laden himself.
Within the past year, Zarqawi has also admitted responsibility for attacks outside of Iraq, including the Jordanian capital of Amman - an act which lost him a great deal of sympathy.
In November 2005 his family placed an advert a newspaper disowning him and absconding from any remaining ties with their son.
"A Jordanian doesn't hit himself with his own spear," the family wrote in the advertisements. "We sever links with him until doomsday."
