Update @ Monday 8:35am ET: Appelbaum has broken his silence on the issue, writing on Twitter unequivocally: "the accusations of criminal sexual misconduct against me are entirely false." He further called the allegations against him "unsubstantiated and unfounded."

He continued:

I think it’s extremely damaging to the community that these character-assassination tactics are being deployed, especially given their ugly history of being used against fellow members of the LGBT community. It pains me to watch the community to which I’ve dedicated so much of my life engage in such self-destructive behavior. Nonetheless, I am prepared to use legal channels, if necessary, to defend my reputation from these libelous accusations.

Original story

Tor Project officials say that one of their most public-facing developers and a member of the "Core Team," Jacob Appelbaum, left the organization on May 25 after "public allegations of sexual mistreatment."

In a statement published Saturday on the Tor Project's website, the organization wrote:

These types of allegations were not entirely new to everybody at Tor; they were consistent with rumors some of us had been hearing for some time. That said, the most recent allegations are much more serious and concrete than anything we had heard previously. We are deeply troubled by these accounts. We do not know exactly what happened here. We don't have all the facts, and we are undertaking several actions to determine them as best as possible. We're also not an investigatory body, and we are uncomfortable making judgments about people's private behaviors.

The statement continued, saying that Tor is "working with a legal firm" specializing in sexual misconduct. The statement added:

People who believe they may have been victims of criminal behavior are advised to contact law enforcement. We recognize that many people in the information security and Internet freedom communities don't necessarily trust law enforcement. We encourage those people to seek advice from people they trust, and to do what they believe is best for them.

After news of Appelbaum's departure spread on Friday, numerous allegations about why he left began to surface on Twitter and later on an anonymous website, whose creators did not immediately respond to Ars' request for comment. Appelbaum has also not responded to Ars’ repeated requests for comment.

Kate Krauss, a Tor Project spokeswoman, told Ars that neither the Tor software itself nor the organization as a whole is in any danger as a result.

The 33-year-old Appelbaum has been a longtime fixture in the privacy and security communities. He was a co-founder of the famed Noisebridge hackerspace in San Francisco in 2007 and first began working with the legendary Cult of the Dead Cow hacker collective in 2008. Over the years, he has spoken multiple times at the Chaos Computer Congress in Germany. In 2013, Appelbaum published various news articles on the National Security Agency (NSA), including one in 2013 revealing that the NSA had been spying on German Chancellor Angela Merkel. Appelbaum also sits on the Technical Advisory Board to the Freedom of the Press Foundation.

In recent years, Appelbaum has lived in Berlin, citing his fear of prosecution and alleged privacy invasions by the American government.