Actress Emma Watson is being targeted by hackers who are threatening to publish nude photos of her in retaliation for her speech where she announced that she was a feminist.
Although the countdown does not specifically say that naked pictures will be published, the site is believed to have been made by members of the internet forum 4chan, who were behind the recent release of hacked pictures of celebrities such as Jennifer Lawrence and Kate Upton.
US website Gawker quoted posts, since deleted, that appear to show the timing of the release is no accident and that the publication of pictures would be a direct response to her speech.
One of the comments quoted says: "She makes stupid feminist speeches at UN, and now her nudes will be online."
The hackers say they will leak nude photos of the Harry Potter star in under five days time.
An image of Emma Watson wiping away a tear appears on the site beside a digital timer which is counting down the seconds until the release.
The words: "Never forget, the biggest to come thus far" are written in capital letters on the bottom of the screen.
Earlier this month Ms Watson came to the defence of her friend Ms Lawrence after dozens of images showing the Hunger Games actress in various states of undress were leaked on 4Chan.
The actress tweeted : “Even worse than seeing women's privacy violated on social media is reading the accompanying comments that show such a lack of empathy.
More than 100 celebrities were affected by the scandal last month after an unidentified hacker stole explicit images and videos from Apple's iCloud service.
Apple said it was "outraged" by the attack and encouraged users to update their accounts with a "strong" password and enable two-step verification.
But over the weekend, celebs including Kim Kardashian, Vanessa Hudgens and Amber Heard were targeted - and more alleged nudes were leaked.
Watson disclosed she became a feminist after being told she was too “bossy” for wanting to direct a play at the age of eight.
Watson, who starred as Hermione in the Harry Potter series, said she had been “confused” at being insulted for wanting to take charge, while boys were allowed to direct without question.
Saying being a “feminist” had initially seemed “uncomplicated” to her, she argued it is now considered “aggressive” and “anti-men” by too many people.
Watson, who has recently become the UN Women Goodwill Ambassador, has now called on women and men alike to reclaim “feminism” for the benefit of all.
In her first major speech, made at the UN headquarters in New York, the actress launched the “HeForShe” campaign, to call on men to speak up for oppressed women everywhere.
Watson, who admitted she may be dismissed by critics who wondered what “this Harry Potter girl” was doing at the UN, asked men to “take up the mantle” to speak up for their “daughters, sisters and mothers”.
The actress, who studied at Oxford and Brown universities, said: “Men—I would like to take this opportunity to extend your formal invitation. Gender equality is your issue too.”
Speaking of her own decision to call herself a feminist, she told an audience: “I started questioning gender-based assumptions when at eight I was confused at being called “bossy,” because I wanted to direct the plays we would put on for our parents—but the boys were not.”
She added she seen her female friends dropping out of sports teams because they did not want to appear “muscly”, while her male peers struggled to express their feelings.
“I decided I was a feminist and this seemed uncomplicated to me,” she said. “But my recent research has shown me that feminism has become an unpopular word.
“Apparently I am among the ranks of women whose expressions are seen as too strong, too aggressive, isolating, anti-men and, unattractive. Why is the word such an uncomfortable one?”
She added: “I was appointed six months ago and the more I have spoken about feminism the more I have realized that fighting for women’s rights has too often become synonymous with man-hating.
“If there is one thing I know for certain, it is that this has to stop.”
The campaign, HeForShe, is described as a “solidarity movement for gender equality that brings together one half of humanity in support of the other of humanity, for the entirety of humanity”.
Watson argued men were also suffering as a result of inequality, enduring mental illness but feeling unable to ask for help for fear of appearing “less macho”.
“Both men and women should feel free to be sensitive,” she said. “Both men and women should feel free to be strong.
“If we stop defining each other by what we are not and start defining ourselves by what we are—we can all be freer and this is what HeForShe is about. It’s about freedom.”
The recently leaked private images of Jennifer Lawrence and Kate Upton, among others, are set to be printed onto life-sized canvases and exhibited at an upcoming event held in Los Angeles.
Photos showing an apparently nude Kim Kardashian are among a group of images that have appeared online in what appears to be a second leak of hacked personal pictures of celebrities, weeks after stars including Jennifer Lawrence and Kate Upton were targeted.