Police have arrested nine people in total as part of their probe
Detectives investigating allegations of fraud at City Hall have arrested three more people.
A 32-year-old man arrested at his home in Peckham, south London, on Tuesday morning, along with a 33-year-old woman have both been released on bail.
A 36-year-old man also arrested by police is being held in custody.
Six other people have been arrested as part of the investigation into fraud allegations concerning organisations given funds by City Hall.
They have all been bailed to return.
Six organisations which received funding from the London Development Agency (LDA), the mayor of London's business arm, are under investigation.
Former mayor Ken Mr Livingstone's race adviser Lee Jasper resigned amid allegations over the misuse of public funds.
An internal inquiry in January cleared him of any wrongdoing, but he was suspended by the mayor pending the police investigation.