US Senator Dan Coats has denied any involvement with the Ku Klux Klan after his name was published alongside other public officials allegedly affiliated with the white supremacist group. Coats was named alongside three other Senators as part an ongoing campaign by the hacktivist group Anonymous to expose the identities of up to 1,000 members of the KKK.

Coats, a Republican Senator serving Indiana, put out a statement on Twitter following the publication of the list. Coats said: "For those who are asking - I have never had any affiliation with the Ku Klux Klan and deplore all forms of racial discrimination." Another politician named on the list, Kentucky mayor Jim Gray, also denied any ties to the KKK.

A hacker by the name of Amped Attacks first published the names of the Senators to the text-sharing site Pastebin. When contacted by IBTimes UK, Amped Attacks said that he had found the email addresses of the Senators in databases held by several KKK sites.

Amped Attacks said: "All I can really say without fully admitting to federal charges is that several databases were dumped from different KKK websites that all linked their emails to the politicians in question and the only way their emails would have been on there to begin with is if they showed support when signing up for [the site] or filled out an application."

What is #OpKKK?

Operation KKK, referred to online as #OpKKK, first began in November 2014 during the protests in Ferguson, Missouri.

When a local chapter of the KKK warned protesters that "lethal force" would be used against them, Anonymous took control of the KKK's main Twitter account and published personal information of alleged members of the white supremacist group.

The campaign has continued in 2015, with Anonymous threatening to reveal the identities of up to 1,000 KKK members on 5 November.

Four separate databases containing contact details of 57 other alleged members of the KKK have also been published as part of Anonymous' Operation KKK.

In a statement released last week as part of #OpKKK's revival, Anonymous stated: "We are not attacking you because of what you believe in as we fight for freedom of speech. Ku Klux Klan, We never stopped watching you. We know who you are. We know the dangerous extent to which you will go to cover your asses. Originally, we did not attack you for your beliefs as we fight for freedom of speech. We attacked you due to your threats to use lethal force in the Ferguson protests.