Police investigating allegations of child abuse at a south-west London guest house in the early 1980s have arrested two men.
The Operation Fernbridge inquiry is looking at claims that senior political figures and others sexually abused boys at the Elm Guest House in Barnes.
Officers held a 66-year-old in Norfolk and a 70-year-old in East Sussex, the first arrests in the investigation.
Police began the probe after receiving information from Labour MP Tom Watson.
Scotland Yard said the allegations are not connected with current residents of the property, which is now flats.
It is also investigating links between the guest house and the now-closed nearby Grafton Close care children's care-home run by Richmond Council.
Commander Peter Spindler, head of the Metropolitan Police's Specialist Crime Investigations unit, said the "complex multi-agency investigation" was supported by the NSPCC charity, the Child Exploitation and Online Protection Centre and Richmond Social Services.
He said anyone affected by, or has information about, activity in the early 1980s at the guest house or care home should contact the NSPCC or police.
In a statement, Richmond Council said it considered "the safeguarding of all children and young people as an utmost priority and we take any allegations of abuse very seriously".
A spokesman added: "We are offering our full support and co-operation to the police during their investigation. As the investigation is ongoing, it would be inappropriate to comment further at this time."