Gwent Police are investigating reports of historic sex offences and the concealment of a birth at a house in Penyrheol.
Police have been seen at the house in Pen-Y-Bryn, Penyrheol, in the last few days and, after enquiries by Caerphilly Observer, have confirmed an ongoing investigation.
A local man is currently assisting police with their enquiries.
Gwent Police Detective Chief Inspector Nicky Brain said: “We are undertaking an investigation at an address in Pen-Y-Bryn, Caerphilly after reports of historic sex offences and a concealment of birth at the address.
“I’d like to reassure residents that this is an isolated case and we are not looking to speak to anyone further during this investigation.”
Gwent Police have said there will be no further comment on the investigation until Monday, April 4.