Investigative reporters, particularly those from tabloid newspapers, will not have slept well last night in the knowledge that the News of the World's royal editor was being questioned by police after an investigation into the interception of phone messages.
Clive Goodman, a long-serving NoW staffer, was arrested last night along with two other men under the Regulation of Investigative Powers Act, which covers the interception of phone records and messages.
Police have been investigating following a complaint made by staff at Clarence House, who had become suspicious that some phone communications were being heard by third parties. After initial inquries, the investigation widened to include other public figures including politicians and celebrities.
Searches were made yesterday at the News of the World's offices in Wapping.
One of the three men, but not Goodman, has been released on police bail, the BBC has reported this morning.
A police statement on Tuesday night said: "Police launched an investigation after concerns were reported to the Met's Royalty Protection Department by members of the Royal Household at Clarence House.
"It is focused on alleged repeated security breaches within telephone networks over a significant period of time and the potential impact this may have on protective security around a number of individuals."
"Police continue to work with the telephone companies concerned and continue to have their full support in attempting to identify any other person whose telephone may have been intercepted."
Article 10 of the Editors Code of Practice, covering clandestine devices and subterfuge, states: "The press must not seek to obtain or publish material acquired by using hidden cameras or clandestine listening devices; or by intercepting private or mobile telephone calls, messages or emails; or by the unauthorised removal of documents or photographs."
More analysis and reaction in this week's Press Gazette.