Rebekah Brooks is believed to be among 11 suspects in the phone-hacking scandal facing criminal charges after police sent their first set of files to prosecutors.
Sources said the former News International chief executive is listed with three other journalists, one police officer and six others in documents handed to the director of public prosecutions.
Keir Starmer QC must now decide whether to go ahead with prosecutions based on police evidence handed to him within the last fortnight.
Starmer said he was facing "very difficult and sensitive decisions" as he predicted more cases were coming his way.
The DPP refused to formally identify who faced charges, saying only that not everyone in the files had been formally arrested.
But sources said details of the files included:
Thurlbeck, who has also been held on suspicion of conspiring to intercept communications, is the only Operation Weeting-related suspect to have been questioned on suspicion of witness intimidation. He is also due to answer bail next week.
All 43 people arrested under the various operations into illegal activities among journalists remain on bail, Starmer added.
Britain's top prosecutor said his new guidelines setting out how journalists may have broken the law would help lawyers with the "very difficult decisions".
"The decisions we are going to make are going to be extremely difficult and extremely sensitive," he said.
"We have got to make a decision because these cases are coming. We cannot duck that... These just happen to be the four files we have got, there may be others. We don't know."
Police launched Weeting, the inquiry devoted specifically to phone hacking, after receiving "significant new information" from News International on January 26 last year.
Elveden was launched months later after officers were given documents suggesting News International journalists made illegal payments to police officers.
The files handed to prosecutors are also understood to cover three other operations, the Sasha perverting the course of justice inquiry, Kilo, an inquiry into police leaks, and Tuleta, the investigation into computer-related breaches.
Under Operation Kilo - the inquiry into police leaks from Operation Weeting - Guardian reporter Amelia Hill was questioned last year under caution.
A CPS spokeswoman said later: "We are not prepared to discuss the identities of those involved or the alleged offences in any greater detail at this stage as a number of related investigations are ongoing.
"We are unable to give any timescale for charging decisions, except to say that these cases are being considered very carefully and thoroughly, and the decisions will be made as soon as is practicable."
Metropolitan Police figures showed that there were 829 potential victims of phone hacking, of whom 231 were said to be uncontactable.
The scandal has already led to the closure of the News of the World after 168 years, prompted a major public inquiry, and forced the resignation of Met Commissioner Sir Paul Stephenson and his assistant John Yates.
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