Four more people have been arrested in an alleged corruption investigation involving police officers, police licensing officers and business owners.
Operation Joseph is investigating allegations of corruption by Westminster Police Licensing Officers and inappropriate relationships between police officers and people running local businesses.
Met police said three men and one woman were arrested on Tuesday (February 23) on suspicion of bribery.
Those arrested are two 36-year-old men, a 60-year-old woman and a 37-year-old man at various addresses across London.
One of the 36-year-old men remains in custody while the remaining three have been released on bail.
It follows six arrests, including a police sergeant and a police constable, on June 24 2015, on suspicion of conspiracy to commit misconduct in public office.
All were bailed pending further enquiries and are due back at police stations in April and May this year.
The sergeant and PC are both suspended.
Further interviews and arrests
Shortly after, on June 30 2015, a 48-year-old woman was interviewed under caution and on July 10 that year a 68-year-old man was interviewed under caution.
Then on August 12 a female police constable, based in Westminster, was interviewed under caution.
The 43-year-old has been placed on restricted duties.
On September 2 a male police constable, also based in Westminster, was arrested on suspicion of conspiracy to commit misconduct in public office.
The 30-year-old, who has been placed on restricted duties, has been bailed pending further enquiries and is next due to return to a police station in mind March.
Operation Joseph is a Directorate of Professional Standards Anti-Corruption Command investigation.
Enquires are ongoing.