Police Commissioner Bernard Hogan-Howe has resumed his Christmas break, Scotland Yard said. Earlier today, the police chief broke off from his holiday to be briefed on the progress of the 'plebgate' investigation, which is being supervised by the Independent Police Complaints Commission.
Andrew Mitchell, who lost his job over claims he called police officers in Downing Street 'plebs', says the allegations were a deliberate attempt to ruin his career.
The former chief whip also said the smears were designed to damage the Conservative Party.
Today the head of Scotland Yard has promised a "ruthless" search for the truth.
Political Correspondent Alex Forrest reports:
Shadow Policing Minister David Hanson has said a "full investigation" into Plebgate is needed.
He said: "It is vital that a full investigation gets to the bottom of this extremely serious issue surrounding what happened at the gates of Downing Street and in the days after as soon as possible.
"The Prime Minister and the Cabinet secretary should have established a credible investigation at the start, as we urged them to.
"It remains a concern that by treating this simply as a media handling issue No 10 and the cabinet office have made this much worse."
Former Justice Nick Herbert has told ITV News it is time the 'Plebgate' incident and the aftermath is "thoroughly investigated".
Lord Fowler is aformer cabinet minister and also MP for Sutton Coldfield before Andrew Mitchell. He says Mr Mitchell should be restored to cabinet as soon as possible, following the 'Plebgate' row'.
Police Commissioner Bernard Hogan-Howe has released the following statement, concerning the Downing Street incident involving Andrew Mitchell and subsequent events.
It reads: "The allegations in relation to this case are extremely serious. For the avoidance of doubt, I am determined there will be a ruthless search for the truth - no matter where the truth takes us.
"This is shown not only by words but by action taken immediately following the receipt of new material earlier this month. This includes:
"My appointment of Deputy Assistant Commissioner Patricia Gallan, head of Professional Standards, to oversee the investigation.
"The allocating of 30 police officers to the task to ensure the investigation is not only thorough but also swift.
"Within 48 hours of receiving new information, the arrest of an officer from the MPS on suspicion of Misconduct in a Public Office, and a few days later a 23-year-old man on suspicion of assisting in that endeavour.
"The broad terms of reference allowing the investigation to develop where the evidence takes it. There was an immediate referral to the Independent Police Complaints Commission and we are committed to keeping them updated as the investigation develops.
"I believe these actions are vital in maintaining public confidence in the police and DAC Gallan and her team have my full confidence to carry out a robust investigation.
"During the last 24 hours I have taken the opportunity to satisfy myself about the welfare of the officers involved. Media interest is to be expected, but for officers to be pursued and identified by the media during an ongoing investigation does, of course, create significant pressure.
"I recognise that there is a great deal of public interest in these events. It is the investigating team who are in the best place to gather and assess all the evidence and it is vital that they are given the time and space to do this."
Metropolitan Police Commissioner Bernard Hogan-Howe today said the force would launch "a ruthless search for the truth" in the Andrew Mitchell "plebgate" row.
In an article in the Sunday Times (£), former Chief Whip Andrew Mitchell has accused the police of destroying his career.
Mr Mitchell described the police log of the 'plebgate' affair as "toxic" and said he was a victim of "police elements".
He also accused the Police Federation of "not telling the truth" in its account of the incident.
Met Commissioner breaks off Xmas holiday citing concerns about welfare of 'plebgate' officers as a paper apparently identifies one.