It is the kind of note a publisher dreads. Dylan Davies, the British contractor whose contested eyewitness account of the assault on the U.S. compound in Benghazi caused a firestorm, sent an email to the publisher of his new book telling them he was going dark.

In the message, which was sent on Friday morning to Simon & Schuster vice president Jennifer Robinson, Davies said someone had threatened to harm his family if he continued to defend his account of events in Benghazi to the media. The email was obtained by The Daily Beast.

The timing could not have been worse. Last week CBS’s 60 Minutes, which had interviewed Davies for a report on Benghazi that aired last month, apologized to its viewers and pulled the report. After 60 Minutes walked away from Davies, Simon & Schuster on Friday announced they would be pulling the book from stores.

In the midst of all of this, Davies has not spoken to the media. Friday’s email, which was sent before Simon & Schuster announced its decision to pull the book, provides some clues on his decision to stop talking.

Davies wrote that on Sunday November 3 at 4:00 a.m., he was hand-delivered a note to his home address in Wales that said, “Stop talking now or your wife and son will disappear.” In the email to Robinson, he went onto say, “Due to this threat I will not discuss the book with anyone under any circumstances for the foreseeable future, I am not prepared to put my family in danger. I stand by my story however I understand that it continues to be rubbished, which I expected.”

Davies wrote that the police took the threat to his family “very seriously” and that he had been advised to leave his home in south Wales and he did not know when he would return.

Rhodri Kendall, a spokesman for the South Wales police, told The Daily Beast that officers were investigating the alleged threat after a complaint was made by Davies. “I am able to confirm that South Wales Police is investigating this allegation,” he said.

Robinson declined to discuss the email sent to Simon & Schuster. A spokesman for 60 Minutes, Kevin Tedesco, did not address the disappearance of Davies in a statement to The Daily Beast. But Davies’s co-author, Damien Lewis, said he was aware of threats to the British contractor and his family.

“I first heard reports of a credible threat to Dylan Davies’s life and that of his family after his real name was made public,” Lewis said. “If he is under such a threat that may help explain his present silence. He remains one of the only eyewitnesses to both the lead up to and the tragic events of the night of Benghazi 9/11 to have spoken out publicly, and that testimony shouldn’t be ruled out without proper scrutiny.”

Since Davies emerged to give his account of the 9/11 anniversary attack at Benghazi, his credibility has been the subject of intense scrutiny. Senior U.S. government officials have told The New York Times and later CBS News that the contractor’s account of the Benghazi attack in his book and on 60 Minutes did not match what he told the FBI. An incident report written for his contractor is also alleged to have contained a different version of the events. The FBI report has not been made public.

Davies told 60 Minutes and said in his book that he scaled the walls of the American compound in Benghazi on the night of the attack and rifle-butted one of the attackers. He also says he was inside the hospital and had confirmed that Ambassador Chris Stevens was dead on the night of the attack while the U.S. government was still looking for him.

Those facts were called into question first by the Washington Post, which published a story based on an incident report from his contractor, Blue Mountain Group. In that report, Davies allegedly said he stayed in his villa during the attack and did not reach the compound until the next morning.

Davies told The Daily Beast this month that he never wrote the report and that his interviews with the FBI and statements given to other U.S. officials matched his version of events.

U.S. officials subsequently told The New York Times and CBS News that his FBI account did not match what he told 60 Minutes. The Daily Beast has not been able to obtain the transcripts of the FBI interviews with Davies or the “302 report” that would summarize what Davies had said. One U.S. official familiar with the Benghazi investigation said Davies was contacted multiple times by the FBI and was considered a credible source about what happened that evening. This source however could not say if the FBI reporting contradicted or confirmed whether Davies rushed to defend the compound or was in the hospital to identify the body of Stevens. A spokesman for the FBI declined to comment for the piece citing an ongoing investigation.

At the end of his email to Robinson, Davies said he understood why his book was being pulled. “Having spoken with Damien this morning I have no problem with the book being taken off the market, I have no way of defending myself at present,” he said. “My reputation has already been ruined in the media and I will never work in the security industry again, this was inevitable due to the sensitive nature of the book, however threatening to kill my family was not something I expected.”

Davies ended his email with these words: “I will not be in touch again for a while, I’m sorry for the trouble this book has caused.”