Julian Assange was arrested yesterday after spending almost seven years living in the Ecuadorian embassy.
The 47-year-old divided public opinion by leaking sensitive information on his whistleblowing website, WikiLeaks.
Here's all you need to know about the controversial figure.
Australian-born Assange worked as a computer programmer before setting up WikiLeaks.
He was born in Queensland in 1971 and studied programming, mathematics and physics at university.
His parents ran a touring theatre.
At the age of 18 he had a son called Daniel, who now works as a software designer.
Assange set up the whistleblowing website in 2006, which published confidential documents, images and video from a wide range of sources.
It made headlines in April 2010 when it published footage showing American soldiers shooting dead 18 civilians in Iraq from a helicopter.
Other notable leaks published on the site include more than 500,000 intercepted pager messages sent during the 9/11 terror attacks, from families checking in on loved ones to government department reactions.
Why was he living in the Ecuadorian embassy?
Assange sought political asylum at the London-based Ecuadorian embassy to avoid extradition to Sweden over a sexual assault case.
He was accused of rape and molestation, but he denies the allegations.
Ecuador granted asylum to Assange in 2012, claiming they feared his human rights could be violated if he was extradited.
However, in October 2018 Assange announced he would be launching legal action against the government of Ecuador, claiming they had violated his "fundamental rights and freedoms".
His asylum status was withdrawn this week, and he was arrested by police on a warrant issued back in 2012 for failing to surrender to the court.
During his time at the embassy, he was visited by the likes of Pamela Anderson, Nigel Farage and former Manchester United forward Eric Cantona.
Why is he facing extradition to the US?
He is facing extradition to the US on charges of conspiring to break into a classified government computer which, on conviction, could attract a maximum jail sentence of five years, according to the US Department of Justice (DoJ).
Details of the charges published by the DoJ show that the charges are linked to the Chelsea Manning episode, a former US intelligence analyst based in Iraq, who shared thousands of classified military files with WikiLeaks.
The US accuses Assange of assisting Chelsea Manning in breaking a password that helped her infiltrate Pentagon computers.
What happens now?
Following his arrest on a provisional arrest warrant, the US has 65 days to submit a full extradition warrant together with an affidavit stating what the charges will be, human rights lawyer Karen Todner said.
His legal team will raise objections and submit arguments on what bars there are to extradition before a full hearing in front of a district judge at Westminster Magistrates' Court, which is likely to take a number of days.