“They threatened to kill peaceful protesters and (Anonymous members) in the Ferguson protest,” the organizer said.

“We want the KKK gone, forever. And that’s what we try to achieve by this. We want race equality,” another #OpKKK organizer, identified on Twitter as @encrypted_six, told Al Jazeera.

Anonymous has taken action on a variety of social justice issues. In 2012 it exposed the names and personal details of people allegedly involved in covering up the rape of a 16-year-old girl in Steubenville, Ohio. This summer, the group took down the Royal Canadian Mounted Police website after an RCMP officer shot and killed a protester wearing a Guy Fawkes mask — a well-known symbol of Anonymous that has been used by the Occupy movement. Because of the group's decentralized nature, there have also been a number of false leaks by individuals posing as members of Anonymous.

On Thursday, Anonymous members with #OpKKK plan to expose the names and other personal details of at least 1,000 people the group says are members of the KKK. The organizer identified as @Anon6k said he was holding part of the list.

Another organizer, @encrypted_six, said, “I have seen the list and I’ve seen a lot more. Some of it does not just contain a simple phone number or an email. Some of the lists contain way more — payment information, family, jobs, addresses.”

“We use cross-point referencing to make sure it’s the right person and that we don’t get the wrong information out in public,” as well as other verification techniques, @encrypted_six said.

It is not illegal to be a member of the KKK or similar groups, and there are no laws preventing KKK members from holding public office or serving as police officers. That lack of screening has been controversial. A police department fired two officers after the FBI linked them to the KKK last year in Fruitland Park, Florida.

The Southern Poverty Law Center, which monitors hate groups in the United States, expressed some skepticism about OperationKKK. Mark Potok, senior fellow at the center, said it was “incredibly dubious” that a high-level public official might be an official member of the KKK. “If a U.S. senator was sympathetic to the views of the Klan, would that person really join, knowing if his membership was exposed it would be instantaneous political death?” Potok said.

The KKK has been on the decline for decades, Potok said. The group’s heyday was in the 1920s, when the Klan had about 4 million members including political leaders and professionals. The group had a slight resurgence in the 1960s in response to the civil rights movement, but still only had about 40,000 members.

“Today, there are probably fewer than 4,000 members, divided up into dozens of squabbling groups,” Potok said. “Today the Klan members are almost universally rural, working-class or below. They tend to be very uneducated, and often the groups are made up of a man, his family, and his neighbors.”

Compared to neo-Nazi groups, racist skinheads or groups who believe in a racist theology called Christian Identity, the Klan is “certainly not the most important or vigorous part of the white supremacist world,” Potok said.

#OpKKK organizers agreed that the KKK is not the only racist organization in the U.S., and said they hope to start a larger conversation with a Twitter discussion on Thursday about race, the Internet and freedom of speech.

Among the questions circulating are: How would you define race? What is dehumanization? How do you balance a community’s best interest and an individual’s civil liberties? Is it possible to protect both without infringing upon either?

On Sunday and Monday, individuals purporting to be members of Anonymous published lists with the names, email addresses and phone numbers of people they said were in the KKK. #OpKKK members disavowed that release, and said those behind it were not related to Anonymous.