'Plebgate': Police officer held over inquiry
A police officer has been arrested by officers investigating claims that a Cabinet minister called police "plebs".
The 46-year-old woman was held in connection with the unauthorised disclosure of information to the media.
Andrew Mitchell quit as chief whip after it was alleged he called police "plebs" - a claim he denies.
The officer is part of the diplomatic protection group and was in Downing Street during the alleged incident. It is the fourth arrest in the probe.
The officer was arrested at her workplace in central London on suspicion of misconduct in a public office.
Meanwhile, Scotland Yard said a 46-year-old police officer from the same unit arrested on Thursday has been released on bail until March and suspended from duty.
He was questioned on suspicion of misconduct in a public office and the unauthorised disclosure of information to the media.
CCTV footage has cast doubt on the original police accounts of the row, which has come to be known as "plebgate".
While Mr Mitchell admits swearing after a police officer refused to let him exit through the main Downing Street gate with his bicycle on 19 September last year, he denies directly swearing at the officer and insists he did not lose his temper or call him a "pleb".
The two other people arrested as part of the inquiry known as Operation Alice have also been released on bail.
A 52-year-old police constable from the diplomatic protection group was arrested on suspicion of misconduct in public office.
And a 23-year-old man, who is not a member of the police force, was arrested on suspicion of "intentionally encouraging or assisting the commission of an indictable offence", relating to misconduct in a public office.