World's most dreaded terrorist Osama bin Laden, known as the mastermind behind the worst-ever terror attack on US soil, has been killed in an operation in Pakistan. Here's a biographical account of Osama's life.

Following is a chronology of Osama's life and his terror operations:

1957: Bin Laden was born in Saudi Arabia. He was the 17th of 52 children of construction magnate Muhammad Awad bin Laden, an immigrant from neighboring Yemen, who runs a construction company, the Saudi bin Laden Group.

1979: The young bin Laden goes to Afghanistan to help Afghan resistance fighters, known as the mujahedeen, repel the Soviet invasion of the country. Bin Laden becomes the chief financier of an organisation, which evolves into a group known as al-Qaeda (the base).

1989: After the Soviets pull out of Afghanistan, bin Laden returns to Saudi Arabia to work for the family construction firm. There he uses his network to raise funds for veterans of the Afghan war.

1991: He is expelled from Saudi Arabia due to his anti-government activities. Eventually, Saudi Arabia revokes his citizenship, and his family disowns him as well. He takes refuge in Sudan.

1993: A bomb at the World Trade Center kills six and wounds hundreds. Six Muslim radicals, who the US officials suspect have links to bin Laden, are eventually convicted for the bombing.

1995: A pair of truck bombs explodes outside the US embassies in Nairobi, Kenya, and Dar es Salaam, Tanzania, killing 224 people.

1996: Under pressure from the US and Saudi Arabia, the Sudanese expels bin Laden from the country. Bin Laden moves with his 10 children and three wives (he is rumored to have since added a fourth) to Afghanistan and declares a jihad, or holy war, against US forces.

November 1998: US court indicts bin Laden for role in embassy bombings, with $5 million bounty offered for his his capture.

1999: The US Federal Bureau of Investigation places bin Laden on its "10 most wanted" list.

October 12, 2000: Suicide bombing of USS Cole in Yemen kills 17 US sailors.

2001: Four of bin Laden's alleged supporters are convicted May 29 of the 1998 bombings of the US embassies in Africa.

2001: Al-Qaeda masterminds September 11 attacks on the twin towers of World Trade Centre and Pentagon, killing more than 3,000 people.

September 13: Following the September 11 terrorism attacks in the United States, the US government names bin Laden as a prime suspect.

September 23: Washington offers a $25 million reward for any information leading to the arrest of bin Laden.

November 13: Afghan opposition forces enter the capital Kabul, marking the beginning of the end for the Taliban regime that sheltered bin Laden.

December 7: US forces fail to kill bin Laden hiding in Tora Bora mountains in Afghanistan. Bin Laden and his forces reportedly escape by mules to Pakistan.

2002: The US-led military operation progresses as the Taliban falls. The allied forces increase ground troops flanked by air support in an effort to rout out hold-out al-Qaeda forces.

March: the battle intensifies in the mountainous terrain of eastern Afghanistan, where reports say bin Laden is located and, according to some, directing troops.

Bin Laden maintains a low profile, but makes headlines again in the fall when al-Jazeera broadcasts two audio tapes featuring what US intelligence officials say are most likely authentic recordings of his voice.

2003: The then Pakistani president Pervez Musharraf says bin Laden is probably alive and hiding in Afghanistan, but claims al-Qaeda is no longer an effective terrorist organisation.

2003: As bin Laden calls Muslims across the world to set aside their differences and join in the "blessed and thankful jihad."

2004: On January 4, al-Jazeera again broadcasts audiotape that CIA officials say is likely a recent recording of bin Laden. On the tape, bin Laden says the US occupation of Iraq is the beginning of an occupation of Persian Gulf states to control their oil reserves.

In March, US defence officials say their forces in Afghanistan will intensify search operations near the Pakistan border, preparing for a broader offensive to hunt down al-Qaeda fugitives, including Osama bin Laden.

2009: US secretary of defence Robert Gates says officials had no reliable information on Bin Laden's whereabouts for "years".

May 2, 2011: President Barack Obama says US forces killed bin Laden in a special operation outside the Pakistani city of Abbottabad.

A US official says an adult son of the al-Qaeda chief was also killed in the operation, which lasted less than 40 minutes.
Source: dnaindia.com