The Welsh model has allegedly been targeted by Manchester United fans after Liberal Democrat MP John Hemming named Ryan Giggs as the footballer she is said to have had an affair with.
The Sun reports that a number of messages on the social networking website have threatened to kill Thomas and some of her family members, including her 2-year-old nephew, who was directly referenced in a tweet.
The Big Brother star, who was branded a "home-wrecking slut", was told: "I wanna hear u scream of fear when u see what i do to u and your family."
"I fear my life is in danger," Thomas is said to have told a friend. "I had to get police involved now they're threatening my nephew. He's the most important thing in my life."
Police are said to have visited Thomas at her North-West London home last night, as a spokesperson confirmed: "Police are investigating an allegation of malicious communications. Inquiries are ongoing."
The paper also claims that Giggs and his wife Stacey have called off a planned trip to Dubai, which they were due to take after this weekend's Champions League final.
Commenting on various tabloid reports, Thomas wrote on Twitter yesterday: "I've not spoken to anyone. So don't believe what u read! (sic)"
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