Julian Assange, leader of the WikiLeaks project that's published extensive secret details of U.S. military and diplomatic activity, has been arrested in London on a Swedish accusation of rape.

"He is accused by the Swedish authorities of one count of unlawful coercion, two counts of sexual molestation, and one count of rape, all alleged to have been committed in August 2010," London's Metropolitan Police said in a statement today.

Assange appeared today at Magistrates Court in the City of Westminster in London, the police said. The police's extradition unit arrested him this morning on a European arrest warrant after Assange and his lawyers arranged to meet with police at a London police station.

Chief Magistrate Howard Riddle denied bail for Assange, saying he deemed Assange to be capable of breaking bail conditions.

Assange has denied the charges, which first surfaced months ago. "The charges are without basis and their issue at this moment is deeply disturbing," he said via Twitter in August.

The arrest is a further serious setback for WikiLeaks, whose actions have incurred the wrath of politicians and pundits but also attracted allies drawn to its cause and disturbed by the response to WikiLeaks.

WikiLeaks said today that despite the arrest, it's continuing with its current project: the release of 250,000 diplomatic cables. "Today's actions against our editor-in-chief Julian Assange won't affect our operations: we will release more cables tonight as normal," WikiLeaks tweeted.

In addition, Assange, an Australian citizen, published an opinion piece in The Australian today. "WikiLeaks is...fearlessly publishing facts that need to be made public," he said. Major news media have published diplomatic cables that WikiLeaks revealed, "yet it is WikiLeaks, as the co-ordinator of these other groups, that has copped the most vicious attacks and accusations from the U.S. government and its acolytes."

Among other recent WikiLeaks difficulties, Swiss bank PostFinance yesterday froze an Assange account with 31,000 euros ($41,340)' the bank said he had "provided false information regarding his place of residence." In a response, WikiLeaks said, "The technicality used to seize the defense fund was that Mr. Assange, as a homeless refugee attempting to gain residency in Switzerland, had used his lawyers address in Geneva for the bank's correspondence."

Meanwhile, MasterCard has stopped processing payments made to WikiLeaks--not long after PayPal did the same. Amazon.com and EveryDNS.net also terminated online services, making it harder for WikiLeaks to stay online.

"I call on any other company or organization that is hosting WikiLeaks to immediately terminate its relationship with them," Sen. Joseph Lieberman of Connecticut said last week. And the incoming chairman of the House Homeland Security Committee wants WikiLeaks listed as a "terrorist" organization.

WikiLeaks still has plenty of allies, though, and many of them have established WikiLeaks mirror sites that have made it harder to keep the WikiLeaks information offline. And a group calling itself Justice for Assange is organizing a protest today at the court.

PayPal suffered a distributed denial-of-service (DDOS) attack over the weekend after its actions, and now the PostFinance bank in Switzerland is under a similar attack. So far the attack has "resulted in more than 11 hours of downtime" for the bank, according to Panda Security, attributing the attack to the so-dubbed Anonymous group. Web monitoring firm Netcraft has also documented the Swiss bank's troubles.

"Preparing to attack Postfinance.ch again, this time with the help of the good people at @Anon_Operation," read one tweet by AnonyWatcher.

Some supporters also are promoting Assange to be Time's 2010 person of the year through online voting. So far, Assange leads the online poll with nearly 250,000 votes.

Updated 4:32 a.m. PT with further information from WikiLeaks. Updated 5:37 a.m. PT with quote from Assange opinion piece. Updated 5:37 a.m. PT with details on DDOS attack on PostFinance. Updated 12:29 a.m. PT on word of Assange being denied bail.