Britain's most senior police officer has become the most significant casualty of the phone-hacking scandal following a day of high drama.
Scotland Yard commissioner Sir Paul Stephenson resigned late yesterday, after News of the World former editor Rebekah Brooks was arrested at a London police station.
She was released on bail until late October after spending 12 hours in custody.
Sir Paul joined a growing list of victims of the controversy, including ex-Downing Street communications chief Andy Coulson, News Corp veteran Les Hinton, former News International chief executive Ms Brooks and the 168-year-old News of the World.
Announcing his resignation, Sir Paul said: "I have taken this decision as a consequence of the ongoing speculation and accusations relating to the Met's links with News International at a senior level and in particular in relation to Mr Neil Wallis, who as you know was arrested in connection with Operation Weeting last week."
David Cameron said he respected and understood Sir Paul's decision, while Home Secretary Theresa May was "sincerely sorry" that he had resigned. Sir Paul insisted his integrity was intact despite pressure on him intensifying over the weekend after it emerged he accepted thousands of pounds-worth of free accommodation at a luxury health spa.
Mrs May is to make a statement to the Commons about the relationship between the Met and Chamy Media, Mr Wallis's PR firm.
Meanwhile, a spokesman for Ms Brooks said the decision to arrest her was "quite a surprise". The 43-year-old was held on suspicion of phone hacking and corruption after keeping an appointment at an unnamed London police station.
Ms Brooks is due to face members of the the Culture, Media and Sport Committee tomorrow to be quizzed about the scandal alongside News International owner Rupert Murdoch and his son James. It is still unclear to what extent she will be able to answer MPs questions if she does indeed appear due to the active criminal proceedings.
Ms Brooks, the former Sun and News of the World editor, resigned as News International chief executive on Friday to avoid distracting attention from the company's efforts to "fix the problems of the past".