Hackers have followed through on a threat to release online a huge cache of data, including customer information, that was stolen a month ago from cheating spouses website AshleyMadison.com, several tech websites reported on Tuesday.

Reuters was not immediately able to confirm the authenticity of the posting. The data was posted onto the dark web, meaning it is only accessible using a specialized browser, although lists of email addresses have since sprouted up on other sites.

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A group calling itself Impact Team had leaked snippets of the compromised data in July and threatened to publish names and salacious details about clients unless Ashley Madison and EstablishedMen.com, another site owned by Toronto-based parent company Avid Life Media, were taken down.

Tech website Wired said 9.7 gigabytes of data was posted, and appeared to include member account and credit card details.

"Avid Life Media has failed to take down Ashley Madison and Established Men," Wired quoted Impact Team as saying in a statement accompanying the online dump.

"We have explained the fraud, deceit, and stupidity of ALM (Avid Life Media) and their members. Now everyone gets to see their data," the hackers said, according to Wired.

Avid Life, which uses the slogan "Life is short. Have an affair", did not immediately respond to emails and phone calls seeking comment.

(Reporting by Alastair Sharp; Editing by Alan Crosby)