British police have arrested WikiLeaks founder Julian Assange on a European arrest warrant that originated in Sweden, where he is wanted for an alleged sex crime. The U.K. received the warrant on Monday afternoon, Eastern Standard Time in the U.S. Assange had threatened, if arrested, to release the encryption key for a large file he says contains damaging U.S. secrets. Here's what we know about the arrest, what comes next, and how people are reacting.

• Assange in British Court Now  The Guardian's Matthew Weaver reported a few minutes before 8 a.m., Eastern U.S. time: "Assange has entered the court. He went in the back entrance and was accompanied by his lawyers Mark Stephens and Jennifer Robinson. They are due to to examine the charges against him. I was on the phone to my colleague Sam Jones, when it happened." The court is in the City of Westminster. CNN describes the charges: "Sweden first issued the arrest warrant for Assange in November, saying he is suspected of one count of rape, two counts of sexual molestation and one count of unlawful coercion--or illegal use of force--allegedly committed in August."

• Will He Be Allowed Bail?  Or will he have to remain in prison? The Guardian's Afua Hirsch writes that "his lawyers are reported to be putting together a generous bail package, including a security of at least £100,000 and a surety--where third parties guarantee to pay the court if he absconds. Experts say a large bail amount is likely to secure bail, although the crime for which Assange is wanted by Sweden is rape, a serious offence for which bail is often harder to secure."

• Can He Beat Extradition?  "Even though the Swedish warrant is a European arrest warrant designed for easy transfer of suspects among European states," reports CNN, "Assange may still choose to fight it--something his London lawyer has promised to do, according to the Press Association. If the court does decide to allow his extradition, Assange will be allowed to appeal that decision." If he is extradited to Sweden, The Guardian's Afua Hirsch says "Assange will be vulnerable to other extradition requests from countries including the US."

• WikiLeaks Vows to Continue Publishing  The Associated Press reports that "the spokesman for WikiLeaks says founder Julian Assange's arrest is an attack on media freedom and that it won't prevent the organization from spilling secrets on the web." Says the spokesman: "this will not change our operation."

• U.S. Should Prosecute Assange Under Espionage Act  Democratic Senator Dianne Feinstein argues in the Wall Street Journal that Assange violated the 1917 Espionage Act by publishing classified material with the intent of damaging U.S. national security. "As for the First Amendment, the Supreme Court has held that its protections of free speech and freedom of the press are not a green light to abandon the protection of our vital national interests. Just as the First Amendment is not a license to yell 'Fire!' in a crowded theater, it is also not a license to jeopardize national security."

Want to add to this story? Let us know in comments or send an email to the author at mfisher at theatlantic dot com. You can share ideas for stories on the Open Wire.