An MSNBC host who covered Donald Trump during the 2016 campaign claimed in her new book that Trump's treatment of the media was comparable to how Christians were executed in the Roman Coliseum.

"They turn as one to boo at us in unison. Six thousand Trump supporters railing against 30 or so journalists — caged in the center of the arena like a modern-day Roman Coliseum," Katy Tur wrote in her book, "Unbelievable: My Front-Row Seat to the Craziest Campaign in American History."

Tur was often the target of Trump's criticism during the 2016 campaign. He often called her "disgraceful," "third-rate," and "not nice," by the GOP nominee during stump speeches.

During a July 2016 campaign stop in Philadelphia, Trump accused the MSNBC correspondent of trying to save Hillary Clinton's campaign when she asked about his past statements calling on foreign governments to hack her emails.

"Be quiet. I know you want to save her," Trump responded to her question.

In her book, Tur accused Trump of turning rowdy crowds against he, to the point where she required a Secret Service escort to her car.

"They turn all at once, a large animal, angry and unchained," she wrote.

"Trump repeatedly singled Tur out. He tried to charm her, intimidate her, and shame her. At one point, he got a crowd so riled up against Tur, Secret Service agents had to walk her to her car," promotional material for Tur's book reads.

She noted the emotional toll covering Trump took on her. "This job is hell. On relationships. On your body. On your mind," she wrote.

Tur recounted how she saw former FBI Director James Comey's reopening of the Clinton email probe as a pivotal turning point in the campaign.

"He's going to win," Tur said she told a colleague. "It's over. He's going to win."