The Metropolitan Police officer faces nine more counts of rape, including possession of a firearm.
David Carrick, 47, was previously charged with 44 offenses against the 12 alleged victims, including rape, coercive and controlling behavior and sexual assault.
He has now been charged with nine further offenses in relation to a thirteenth alleged victim.
The new charges are false imprisonment, six counts of rape, indecent assault and possession of a firearm with intent to cause fear of violence. The charges relate to alleged incidents that took place in 2003 and were reported to the police in July 2022.
The allegation regarding firearm possession predates Carrick’s service in an armed police role.
He will appear at Westminster Magistrates’ Court on 30 November.
His remand is still on.
Carrick was initially arrested in October 2021 by Hertfordshire Constabulary.
He was immediately suspended and Herts Police launched an investigation.
Prior to his suspension, he was attached to the Parliamentary and Diplomatic Security Command.
A police statement said: “As the investigation progresses referrals have been made to the independent Office for Police Conduct.
“The Commercial Standards Directorate continues to closely monitor developments and will provide whatever assistance they can to Hertfordshire authorities. National rules dictate that any misconduct proceedings must await the outcome of a criminal case.