20 years since the 9/11 attacks shook the world
It's two decades since nearly 3,000 people were killed in New York, the Pentagon and in Pennsylvania
Today marks the twentieth anniversary of the 9/11 terror attacks in America which shook the world.
Two planes were hijacked and flew into the World Trade Centre's twin towers in New York, another was flown into the Pentagon in Washington and another crashed in Pennsylvania.
2,750 people were killed in New York, 184 at the Pentagon and 40 people on board the plane in Pennsylvania with 67 Britons amongst the dead.
Twenty years on the incidents have not been forgotten and today there are a number of memorials taking place across the world.
How events unfolded on 11th September 2001
Four aeroplanes were hijacked by nineteen Al-Qaeda militants on September 11th. Here's a timeline of events on that awful day.
8.45am (1.45pm UK time): The first plane hit the World Trade Centre's north tower, trapping everyone on the floors above.
9.03am (2.03pm): The second plane crashed into the south tower 18 minutes later.
9.37am (2.37pm): A plane crashes into the Pentagon building in Washington, the headquarters of the United States Department of Defence.
9.59am (2.59pm): The south tower of the World Trade Centre collapses in New York.
10.03am (3.03pm): A fourth hi-jacked plane crashed after passengers fought four Al-Qaeda terrorists who had taken control of the plane. No-one on board the plane survived, but they almost certainly stopped it being used to hit another building.
10.28am (3.28pm): The north tower in New York collapses, half an hour after it's twin.
What it's like losing your Dad in the 9/11 terror attacks
"I don't think there was anything my dad enjoyed more than being a dad"...
42-year-old Robert Sliwak was working as a bond broker on the 105th floor of the North Tower.
His son Ryan, now 28, told us how his mum broke the news to him and his siblings that his dad wasn't coming home.
"It was the day after my eighth birthday, on the 15th September. My mum took me and my brother and sister to the local park and sat us down and told us that our dad died and he wasn't coming home."
"Even after 20 years it just doesn't get any easier".
Boris Johnson says 9/11 attackers failed to undermine freedom and democracy
The 9/11 terrorists failed to undermine the faith of “free peoples” around the world in open societies, Boris Johnson has said.
In a defiant message to mark the 20th anniversary of the attack by al Qaida on the Twin Towers in New York, the Prime Minister said that while the threat remained people refused to live their lives in “permanent fear”.
READ MORE: "I should never have survived that day" - North Yorkshire filmmaker who escaped Twin Towers collapse
In his address, which will be played to a memorial event at the Olympic Park in east London on Saturday, he said recent events in Afghanistan had only strengthened people’s belief in freedom and democracy.
“Twenty years ago, September 11 2001 became, in President Roosevelt’s words after Pearl Harbour, a ‘date which will live in infamy’,” he said.
“On a crystal clear morning, terrorists attacked the United States with the simple goal of killing or maiming as many human beings as possible, and by inflicting such bloodshed in the world’s greatest democracy, they tried to destroy the faith of free peoples everywhere in the open societies which terrorists despise and which we cherish.
“And it is precisely because of the openness and tolerance of the United States that people of almost every nationality and religion were among the 2,977 murdered on that day, including 67 Britons, each of them a symbol of the eternal friendship between the United Kingdom and the United States.
READ MORE: 'It could have been me running to a burning building' - why 9/11 needs to be remembered
“But while the terrorists imposed their burden of grief and suffering, and while the threat persists today, we can now say with the perspective of 20 years that they failed to shake our belief in freedom and democracy; they failed to drive our nations apart, or cause us to abandon our values, or to live in permanent fear.
“The fact that we are coming together today – in sorrow but also in faith and resolve – demonstrates the failure of terrorism and the strength of the bonds between us.