Four planes, 19 hijackers and 2,819 dead: the facts about September 11, 2001 still have the power to shock.

On the morning of September 11, 2001, the world woke up as normal. In New York, 50,000 people made their way to work in the Twin Towers that had been standing proudly over Manhattan since 1970. At 7.59am, 92 passengers and crew took off on American Airlines Flight 11 from Boston, Massachusetts bound for Los Angeles.

At 8.46am Eastern Standard Time (EST), that same plane crashed into the World Trade Center North Tower, killing everyone onboard instantly, as well as an unknown number of people who were sitting at their desks. Three minutes later, images of the gaping hole between the 92rd and 98th floors of the building were beamed across the USA by CNN. People watching, including office workers in the neighbouring tower, gasped at what seemed a terrible accident. Helpless, they watched the infernal aftermath.

The BBC began its coverage at 8.58am EST, so Britain was tuned in when, just after 2pm here, a second plane flew into the South Tower with 65 people on board. It hit lower this time, between the 77th and 85th floors. Only four people on the floors above made it to safety, down the only intact stairwell. It became instantly clear that this was no accident. President George W Bush confirmed this at 9.30am EST, calling it an “apparent attack on our country” in his address to the nation.

Just half an hour later, the South Tower collapsed. It was followed by the North Tower, 29 minutes later. The fires were so intense they burned for 99 days at what would be called Ground Zero; 1,616 death certificates had to be issued without bodies despite a 230-day search. Phone lines jammed as people called friends and family inside the towers. They saw bodies fall from the burning buildings and prayed they wouldn’t recognise a husband or father (male fatalities outnumbered women 3:1). We now know that some on the upper floors jumped, driven out by the extreme heat and suffocating smoke. The descent from top of the building took 12 seconds and those near the scene described the window-shaking impact as they hit the ground. One firefighter was killed by a falling body, and a further 343 firefighters and paramedics died on the scene, alongside 23 NYPD officers.

9/11: The day the world changed