'You are under surveillance': Operation Weeting detective warns Elle Macpherson aide during lunch meeting

Mary-Ellen Field, former business aide to Elle Macpherson (Getty Images)

Detectives have launched a stalking investigation after Mary-Ellen Field, the former business aide to the Australian supermodel Elle Macpherson, lodged a complaint that she has been put under surveillance by private investigators.

Ms Field, who recently withdrew her long-standing phone-hacking claim against News International (NI) and faces costs of more than £75,000, contacted the police at the end of May after a meeting with a senior detective working on Operation Weeting, the specialist Metropolitan Police unit investigating illegal phone interceptions. The Met detective raised the suspicion that someone was watching them during their meeting at a restaurant in Putney on 21 May.

A complaint which described the meeting was lodged at Wimbledon police station. A description of the individual suspected of being involved in the surveillance, and the subsequent advice from the Weeting detective on how Ms Field could lose the man tailing her, was contained in the report. The surveillance operation is suspected to have lasted until at least 25 May.

The Met confirmed that Ms Field's report had been passed to Wandsworth CID and that an investigation had been launched. The Met said no arrests had so far been made. The suspected identity of one of the surveillance team is being looked at by Scotland Yard, which is also examining CCTV footage from Putney.

The man, a freelance private investigator based in Sussex, is suspected of being hired to follow Ms Field. For legal reason he cannot be named.

Through intermediaries in the private security industry, and through contact made with the founder of a specialist close protection firm who worked with the investigator, the IoS asked for details of the alleged surveillance, who else was involved and who had hired them. No answer was received.

Ms Field was described at the Leveson inquiry as "collateral damage" from the phone hacking scandal that has so far cost Rupert Murdoch's now-divided global news and television empire millions of pounds in settlement and legal costs to victims of the News of the World's (NOTW) illegal hacking culture. Ms Macpherson was identified at the first 2007 phone hacking trial as one of a handful of the newspaper's victims.

Ms Field's case against NI suggested she had been blamed by the model for personal information that had appeared in NOTW stories. However, she withdrew her claim against NI after being unable to present evidence that the NOTW hacking Ms Macpherson's phone was behind her dismissal as the model's business manager. There is no suggestion that the Putney investigator was in any way connected to NI.

It was revealed last week that in secret recordings made inside NI's London headquarters, Mr Murdoch said the police's investigation into his UK titles was "totally incompetent" and a "disgrace". He also revealed there had been a shift in the level of co-operation with the investigation, and that no internal company documents had been handed to the police "for months".