9/11 anniversary: Some facts you need to know about the attacks that shook the world

September 11, 2001, a black day that shook the whole world. A massive attack was launched by the Islamist terrorist in US. It is regarded as the worst terror attacks that shook the world.

The attacks resulted into massive destructions and deaths, it triggered major initiatives by US to combat terrorism a global menace.

The attacks was alleged retaliation for US's support of Israel, its involvement in the Persian Gulf War and its continued military presence in the Middle East.

Here are some facts about the devastating attacks in US

• It was September 11, 2001 when 19 hijackers took control of four passenger jets flying above US.

• Two of the four hijacked jets deliberately hit the twin towers of World Trade Centre in New York, considered to be symbol of power and influence of US.

• A third plane hit the Pentagon just outside Washington, D.C., and the fourth plane crashed in a field in Pennsylvania.

• 19 hijackers were among 3000 people killed in the attack carried out by Osama Bin Laden led Al-Qaeda.

• 9/11 came as biggest terrorist attack in US. Country faced worst loss of life due to terror attack on its soil.

• It took firefighters 100 days to extinguish all the fires ignited by the attacks in New York.