The texts sent from Sanchez's phone to her brother Michael Sanchez in 2018 include a flirtatious message from Bezos and a shirtless photo of him, the Journal reported, citing people familiar with the matter.

The text messages are part of evidence gathered by federal prosecutors in Manhattan as they investigate whether the National Enquirer's publisher, American Media Inc. (AMI), tried to extort Bezos.

While prosecutors continue to investigate, no one, including Lauren and Michael Sanchez, has been charged with a crime.

CNN Business has previously reported that Michael Sanchez provided the National Enquirer with information about his sister's extramarital affair with Bezos. The tabloid published its story about the affair shortly after Bezos and his wife, MacKenzie, announced their divorce last January.

The Amazon CEO subsequently published a blog post accusing American Media of "extortion and blackmail."

People close to Bezos have suggested that Saudi Arabia was behind the leak of his private information. "Our investigators and several experts concluded with high confidence that the Saudis had access to Bezos' phone, and gained private information," Gavin de Becker, a security consultant hired by Bezos, wrote in an opinion piece published by the Daily Beast in March 2019.

Those allegations resurfaced earlier this week when media outlets, including CNN Business, reported that a forensics team hired by Bezos had concluded that the CEO's mobile phone had been compromised and that the hack originated from an account controlled by Saudi crown prince Mohammed bin Salman. A source told CNN that the forensics team had reached its conclusion with "medium to high" confidence. The story was first reported by The Guardian.

Saudi Arabia denied on Tuesday that it was responsible for any such hack. The Saudi embassy in Washington wrote on Twitter that "recent media reports that suggest the Kingdom is behind a hacking of Mr. Jeff Bezos' phone are absurd."

AMI has denied any links to Saudi Arabia.

A spokesman for the company previously said, "American Media does not have, nor have we ever had, any editorial or financial ties to Saudi Arabia." An attorney for American Media CEO David Pecker, Elkan Abramowitz, said in February that the source for the tabloid's story was "not Saudi Arabia."

Michael Sanchez declined to comment to the Wall Street Journal on the texts or his interactions with American Media. He denied to the Washington Post that he played a role in leaking details about the relationship, and told CNN Business, "I have been told that the Amazon investigation determined that I was not involved in the leak of the d*ck pics, because I never had access to any of the d*ck pics."