Anonymous target revenge porn site owner Hunter Moore
The former owner of a "revenge porn" website has been threatened by hacktivist collective Anonymous.
Hunter Moore used to post sexual images of men and women without their permission, along with links to their social networking profiles.
Mr Moore said he will launch a new site soon, telling one technology blog he would also post home addresses.
He later said he was "misquoted", but Anonymous has said he must be held "accountable for his actions".
"We will protect anyone who is victimised by abuse of our internet, we will prevent the stalking, rape, and possible murders as by-product of his sites," the group said in a media release.
It added: "Operation anti-bully. Operation hunt Hunter engaged. We are Anonymous, we are legion, we do not forgive, we do not forget, Hunter Moore, expect us."
Mr Moore sold his old website, IsAnyoneUp.com, to an anti-bullying charity in April this year.
Until that point it had gained notoriety for publishing pornographic pictures of men and women from all over the world, sent in by disgruntled ex-boyfriends and girlfriends.
So-called "revenge porn" is common online, but Mr Moore's site angered anti-bullying campaigners further due to the inclusion of links to social networking sites - leaving victims open to large levels of abuse.
People who had made requests for the photographs to be removed were often ridiculed further, and the huge majority of legal threats against Mr Moore were ignored.
"I sold it because I hated what the media turned it into and it could never be what I wanted it to be," Mr Moore has said about the closed site, which reportedly made him about $20,000 (£12,400; 15,335 euros) a month from advertising revenue.
Speaking about his new venture, which has not yet launched, he said: "This time I am doing it right. I am creating something that will question if you ever want to have kids.
"I am making something very scary but yet fun."
Mr Moore told technology blog Betabeat's Jessica Roy that the new site would "introduce the mapping stuff so you can stalk people", but in a subsequent interview with Salon magazine he took back the comment, stating that he made it while "drunk".
Regardless of his intentions, Anonymous published details about Mr Moore online, including the names of family members and his home address.
The group posted a video about their actions to Vimeo. In it, they showed pictures of Amanda Todd - a girl who committed suicide after topless photographs of her were circulated on the internet.
Prior to her death, 15-year-old Miss Todd created a YouTube video describing how she was bullied.
Mr Moore, who has said his new site has had thousands of submissions, has in the past said he holds no guilt over what he does.
"It's anonymous to me. I don't know the people - it's just a little picture on a screen," he told the BBC in an interview in April.
"If you're just crying over some [picture] you sent to some boy you just met, no I'm not going to take it down, and no I don't really care."