A police officer has been sacked following the investigation into the "plebgate" row in Downing Street, Scotland Yard said.
Susan Johnson, a serving police constable with the diplomatic protection group, has been dismissed today without notice after a gross misconduct case against her was found to be proven, the Met said.
"A police officer has today, May 21, been dismissed from the Metropolitan Police Service (MPS) without notice after a gross misconduct case against her was found to be proven following the Operation Alice investigation," a statement from Scotland Yard said.
"The gross misconduct hearing was held before a panel made up of an independent representative, a superintendent and chaired by commander Julian Bennett.
"The panel found the case against Susan Johnson proven as she had breached standards of professional behaviour in relation to honesty and integrity; confidentiality; discreditable conduct and challenging and reporting improper conduct."
The "plebgate" row erupted after Cabinet Minister Andrew Mitchell launched into a foul-mouthed outburst when he was denied permission to cycle through the main gate at Downing Street on September 19 2012.
He and the gate officer Pc Toby Rowland gave conflicting accounts of what happened, with the officer claiming the politician used the word ''pleb'', something Mr Mitchell has always denied.
Pc Keith Wallis, a Metropolitan Police diplomatic protection officer, was jailed after he admitted lying about witnessing the row that ultimately led to the resignation of the former cabinet minister.
Scotland Yard said Pc Johnson, who was not on duty at the time of the incident in Downing Street, was arrested on July 3 on suspicion of misconduct in a public office.
She was told by the Crown Prosecution Service on November 26 that she would face no further criminal action.
The Met said they had then proposed - and the Independent Police Complaints Commission (IPCC) had agreed - that Pc Johnson had a case to answer for gross misconduct.
"The officer was not on duty at the time of the incident at Downing Street," the statement said.
"The Operation Alice team found evidence that a person closely connected to Susan Johnson contacted The Sun newspaper on September 20 and that around that time the two exchanged text messages and a phone call.
"The team found further evidence that later that same day Keith Wallis emailed Susan Johnson a copy of the email that he had sent to his MP falsely claiming to have witnessed the incident at Downing Street.
"On September 25 Keith Wallis told Susan Johnson that he had had a meeting with his MP. At no time did she report the matter to a senior officer.
"She has been suspended from duty since the time of her arrest."
Pc Gillian Weatherley was sacked at the end of April over leaks to the press linked to the Plebgate row.
She was on duty in Downing Street on the day of the confrontation between Mr Mitchell and Pc Rowland.
The next day, Weatherley sent a photograph of an email Pc Rowland had sent to his bosses about the row to another officer, James Glanville, who was later sacked for leaking the information to the Sun newspaper.
Scotland Yard said one further gross misconduct case remained as a result of the Operation Alice investigation, scheduled to take place today and Friday. The outcome of the hearing will be made public.