France, Sept. 11 -- On 11 September 2001, Al-Qaeda hijackers seized control of two planes that struck the two World Trade Center towers in downtown New York City.

A third hijacked jet smashed into the Pentagon, and a fourth plane that appeared to be headed for the US Capitol or the White House crashed in woodland near Shanksville, Pennsylvania, after passengers fought back and seized control.

The attacks claimed the lives of 2,977 people, mostly in the collapse of the Twin Towers on the site now known as Ground Zero.

But in the last 25 years, thousands of people who escaped or participated in rescue operations have developed serious illnesses associated with exposure to toxic dust and debris. Seventh silence

More than 9,400 have died ...