The arrest relates to a video which was circulated online and came to the attention of police just before 23:30hrs on Wednesday, 30 March. The PCSO, who is attached to the Met’s Roads and Transport Policing Command, remains in custody. Commander Kyle Gordon, who is in charge of the Met’s Roads and Transport Policing Command, said: “I know that everyone will be absolutely shocked by this video. I am absolutely horrified and saddened by incidents such as this, as are all decent officers and staff. They are contrary to everything we stand for. “I would like to reassure everyone that we are working as fast as we possibly can to identify the full circumstances of what took place. “As soon as we became aware of the video just before midnight we acted immediately. Officers worked throughout the night and a serving member of police staff was arrested in the early hours of this morning and taken into custody. “As a criminal investigation is now under way we are limited in what further details we can discuss. However, we will keep the public updated at significant stages of the inquiry.” The Met’s Directorate of Professional Standards is leading this investigation and a referral has been made to the Independent Office for Police Conduct.