The second plane about to hit second tower during the September 11, 2001 terrorist attack on the World Trade Centre in New York. AP

The hijacked plane about to hit second tower during the September 11, 2001 terrorist attack on the World Trade Centre in New York. AP

The second plane moments before it slams into the second tower of the World Trade Centre, on September 11, 2001. AP

The second tower explodes into a fireball after the terrorist attack on September 11, 2001. AP

The twin towers of the World Trade Centre burn after hijacked planes crashed into them in New York on September 11, 2001. AP

Smoke billows from the burning twin towers before they collapse, on September 11, 2001. AP

The south tower begins to collapse after the September 11, 2001, terrorist attack on the World Trade Centre. AP

The moment US President George W. Bush learned of the 9/11 twin tower attacks from his then Chief of Staff Andrew Card. He was reading to school children at the time. AFP

These never before seen pictures show the North Tower on fire. ABC News in the US recently obtained these images through Freedom of Information Act request in 2009 with the National Institute of Standards and Technology. Picture: Det. Greg Semendinger/NYC Police Aviation Unit.

ABC News in the US recently obtained these images through Freedom of Information Act request in 2009 with the National Institute of Standards and Technology. Picture: Det. Greg Semendinger/NYC Police Aviation Unit.

The dust and debris is about to invade New York after the attack. ABC News in the US recently obtained these images through Freedom of Information Act request in 2009 with the National Institute of Standards and Technology. Picture: Det. Greg Semendinger/NYC Police Aviation Unit.

The dust and debris is about to invade New York after the attack. ABC News in the US recently obtained these images through Freedom of Information Act request in 2009 with the National Institute of Standards and Technology. Picture: Det. Greg Semendinger/NYC Police Aviation Unit.

The dust and debris is about to invade New York after the attack. ABC News in the US recently obtained these images through Freedom of Information Act request in 2009 with the National Institute of Standards and Technology. Picture: Det. Greg Semendinger/NYC Police Aviation Unit.

The dust and debris is about to invade New York after the attack. ABC News in the US recently obtained these images through Freedom of Information Act request in 2009 with the National Institute of Standards and Technology. Picture: Det. Greg Semendinger/NYC Police Aviation Unit.

The dust and debris is about to invade New York after the attack. ABC News in the US recently obtained these images through Freedom of Information Act request in 2009 with the National Institute of Standards and Technology. Picture: Det. Greg Semendinger/NYC Police Aviation Unit.

Pedestrians run from the scene as one of the World Trade Centre Towers collapses in New York on September 11, 2001. AFP

This iconic image from September 11, 2001 shows a man holding a small fire extinguisher, standing in the rubble, and calling out asking if anyone needs help, after the collapse of the first World Trade Centre Tower in New York City. AFP

Firefighters working in rubble of World Trade Centre on September 11, 2001. AP

Firefighters making their way through the rubble of the World Trade Centre in New York after two hijacked planes flew into the landmark skyscrapers on September 11, 2001. AFP

Firefighters raise the American flag among the wreckage of the World Trade Centre on September 11, 2001. AP