LONDON - WikiLeaks founder Julian Assange was arrested and jailed without bail yesterday in a sex-crimes investigation, but his organization scarcely missed a beat, releasing a new batch of the secret cables that U.S. officials say are damaging America's security and relations worldwide.

A month after dropping out of public view, the 39-year-old Australian surrendered to Scotland Yard to answer a warrant issued for his arrest by Sweden. He is wanted for questioning after two women accused him of having sex with them without a condom and without their consent.

Assange said that he would fight extradition to Sweden, setting the stage for what could be a pitched legal battle. And as if to prove that it can't be intimidated, WikiLeaks promptly released a dozen new cables, including details of a NATO defense plan for Estonia, Latvia and Lithuania that made Russia bristle.

WikiLeaks spokesman Kristinn Hrafnsson insisted that Assange's arrest and the decision yesterday by both Visa and MasterCard to stop processing donations to the group "will not change our operation." Hrafnsson said that the organization has no plans yet to make good on its threat to release en masse some of its most sensitive U.S. documents if it comes under attack.

At a court hearing in London, Assange showed no reaction as Judge Howard Riddle denied him bail while he awaits an extradition hearing Dec. 14.

The U.S. government is investigating whether Assange can be prosecuted for espionage or other offenses, such as receiving stolen goods. Yesterday, Pentagon and State Department officials said that some foreign officials have suddenly grown reluctant to trust the U.S. because of the secrets spilled by WikiLeaks.

During the hour-long court hearing in London, attorney Gemma Lindfield, acting on behalf of the Swedish authorities, outlined the allegations of rape, molestation and unlawful coercion that were brought against Assange following separate sexual encounters in August with two women in Sweden.

Lindfield said that one woman accused Assange of pinning her down and refusing to use a condom on the night of Aug. 14 in Stockholm. That woman also accused of Assange of molesting her in a way "designed to violate her sexual integrity" several days later. A second woman accused Assange of having sex with her without a condom while he was a guest at her Stockholm home and she was asleep.

A person who has sex with an unconscious, drunk or sleeping person in Sweden can be convicted of rape and sentenced to two to six years in prison.

Assange's lawyers have claimed that the accusations stem from disputes "over consensual but unprotected sex," and they say that the women made the claims only after finding out that Assange had slept with both.

Prosecutors in Sweden have not brought any formal charges against Assange, and WikiLeaks lawyer Mark Stephens said that there are doubts as to whether Sweden has the legal right to extradite him simply for questioning.