Arron Banks's private Twitter messages leaked by hacker

Arron Banks’s Twitter account has been hacked and the entire private message history of the Leave.EU founder uploaded to the internet, in what appears to be a targeted attack that has been reported to the police.

The founder of the pro-Brexit campaign group, who has been the subject of questions about the source of his group’s funding and rule breaches during the EU referendum, confirmed the hack and accused Twitter of leaving his personal data available for anyone to access for almost 24 hours.

Leave.EU spokesman, Andy Wigmore, told the Guardian the hack had been reported to the police and they were investigating possible breaches of the Computer Misuse Act.

“The police told us pretty quickly that it was a simswap,” he said, referring to the tactic where control of a phone number is obtained by a hacker, enabling them to gain access to the account.

The attack appears to have involved gaining access to Banks’s email address, which was registered to an expired campaign website. Someone else appears to now own the domain for that site, which directs users to pornography.

Wigmore said he and Banks had been unable to download the hacked messages due to a lack of technical skills. However, they had been sent some by others who had managed to download them. Wigmore dismissed the content as “gossip” rather than revelations. He also criticised Twitter for the time it took the social media platform to respond to the data breach.

Banks has previous experience of the UK’s data laws. Earlier this year the information commissioner launched an audit into both Leave.EU and Banks’s insurance company, fining the organisations a total of £120,000 for data protection violations during the EU referendum campaign.

In recent weeks Banks has split with Nigel Farage over tactics, and his Leave.EU campaign has instead swung behind Boris Johnson’s Conservative party, promoting the prime minister’s policies.

Wigmore said he and Banks were increasingly spending their time away from politics, working on a business growing hemp for CBD products in central America, dubbing themselves the “Breaking Bad Boys of Brexit”.

“We’ve gone into hemp in a big way because it’s Belize and gets six harvests a year. It’s not cannabis, you can’t get high on it,” he said.

Screengrabs of Banks’s private Twitter exchanges with journalists and pro-Brexit campaigners have already begun circulating – on Twitter.

However, in a sign of the confused online information landscape, fake messages purporting to be from the leak have also been circulating. One account that published false information included the remain campaign group Our Future, Our Choice, which shared a fabricated conversation between Banks and a senior Tory cabinet minister.

A spokesperson for Avon and Somerset police said: “We are investigating whether any offences have been committed under the Computer Misuse Act after we received a report that a Twitter account was compromised.”