Hello, and welcome to IBTimes' live blog of the Paris Unity March. More than 1 million people are gathering at the Place de la Republique, in a rally against this week's terror attacks that killed 17 people, including two police officers, which began on an attack on the satirical newspaper Charlie Hebdo.
German Chancellor Angela Merkel, Palestinian Chairman Mahmoud Abbas, and Prime Ministers Benjamin Netanyahu and David Cameron, are amongst the 40 world leaders attending the march.
If you would like to send us photos and videos of the march from your perspective, you can reach us on Twitter by mentioning @IBTimesUK.
5:45pm: French Interior Ministry says Paris rally for unity against terrorism was the largest demonstration in France's history.
Calling the rally "unprecedented," the ministry said the demonstrators were so numerous they spread beyond the official march route, making them impossible to count.
French media estimated up to 3 million took part, with leaders from more than 40 nations present.
5:28pm: March beginning to wind down, as French officials state that up to 1.5 million people attended, more than the crowd who celebrated liberation in 1944. At least 700,000 more joined vigils in other cities across France.
World leaders including Muslim and Jewish statesmen linked arms to pay tribute to victims of Islamist militant attacks. Paris police said the turnout was peaceful and "without precedent".
5:19pm: Danish Prime Minister Helle Thorning-Schmidt (C) took an unfortunate tumble as she tripped up on the stairs at the Elysee Palace after attending the Unity rally.
5:04pm: British Prime Minister David Cameron has tweeted his reflections after attending the Unity March in Paris today.
4:53pm: As many as 1.5 million people have attended the Paris Unity March today, according to AFP. Local organisers also told AFP that over one million people have attended marches in French towns outside the capital.
4:49pm: In Paris, Stephen Fry has tweeted a photo from a side street, packed with people desperately trying to get to the march.
4:44pm: The Tricoleur has been projected onto the National Gallery in London. La Marseillaise is now being raucously belted out by the large crowd.
4:38pm: At Boulevard Voltaire, a banner is being carried, emblazoned with a famous quote from Dr Martin Luther King: "We must learn to live together as brothers or perish together as fools."
4:33pm: According to AFP, President Francois Hollande has reportedly met with the family of Ahmed Merabet, the police officer who was shot dead by the Kouachi brothers outside the offices of Charlie Hebdo.
4:21pm: "I am a target" - An anonymous French police officer shows his support for the victims of the Paris shootings.
4.00pm: At today's Rome derby, Lazio's players expressed their solidarity, with Je Suis Charlie shirts.
3.50pm: Some have attacked the hypocrisy of Russia's foreign minister Sergei Lavrov in attending today's march, with a man reportedly arrested in Moscow for raising a Je Suis Charlie placard last night.
"There is a disconcerting irony in Russian Foreign Minister Sergei Lavrov attending the rally in Paris today when freedom of speech is so curtailed, not permitted and replaced by fantastical propaganda in Russia" one demonstrator told the BBC.
A silent march in Moscow today though has reportedly gone ahead without incident.
3.43pm: As the crowd slowly makes its way along the route, there is spontaneous applause as banners are held aloft with slogans celebrating liberty and unity.
3.30pm: Protesters hold Je Suis Ahmed signs, in memory of Muslim police officer Ahmed Merabet, killed in the attacks on Charlie Hebdo.
3.23pm: Protesters are using pencils as symbols of the right to freedom of speech.
3.17pm: "When I grow up I'll be a journalist, I'm not afraid," reads the message held aloft by a girl, after last week's attack on French satirical magazine Charlie Hebdo.
3.00pm: Flags from different countries show the number of nations represented at the solidarity march this afternoon, with the Ukrainian and Georgian flags flying amidst the tricoleur.
2:44pm: IBTimes's own Jack Moore reports from Trafalgar Square.
"It's a sombre occasion but also one of defiance with several thousand Londoners and French nationals taking to the square.
Moments of silence were followed by chants of "Nous sommes Charlie" and a number of French songs.
An applause was also held for Boris Johnson in appreciation of his decision to illuminate a number of London landmarks."
2:30pm: At the Trafalgar Square march deputy PM Nick Clegg will attend along with French Ambassador to the U.K., Sylvie Bermann. After the event famous landmarks across London will be lit up in the colours of the French flag as a memorial to those killed this week.
2:14pm: spontaneous applause has broken out and some of the crowd are singing the French national anthem, according to eye-witnesses. As IB Times reported earlier, 2,000 police officers have been deployed to help safeguard the rally.
1:57pm: David Cameron tells BBC News: "We're here to demonstrate that we all stand for values of democracy, of freedom, of freedom of expression, of tolerance. But there's also something else - which is that we in Britain face a very similar threat, a threat of fanatical extremism and we have to confront that in every way we can."
1:38pm: The four shoppers murdered at a kosher supermarket on Friday will be buried on Tuesday in Israel, according to AFP. They have been named as Yoav Hattab, Philippe Braham, Yohan Cohen, and Francois-Michel Saada.
1:36pm: Dozens of heads of state file out of the Élysée Palace on to the streets of Paris to take part in the march, as a light rain starts falling.
1.22pm: French Interior Minister Bernard Cazeneuve tells reporters that his whole country was ''in mourning''.
1:07pm: Thousands of people are already gathering for the march
— Magnus McGrandle (@magnusmcg) January 11, 2015
1:00pm: British Prime Minister David Cameron travelling to Paris
I'm on my way to Paris to march with the French people. The #CharlieHebdo murders will not crush our spirit or our values.
— David Cameron (@David_Cameron) January 11, 2015