A poster is being circulated to campsites in France

Detectives have confirmed they are following a new lead in their hunt for a missing four-year-old from mid Wales.

Four weeks have passed since Estelle Clayton from Brecon - known as Esti - was abducted by her father Simon Clayton and taken abroad.

But on Wednesday police said they had received a possible sighting of her in southern France.

News of the sighting - which was 11 days after Esti disappeared - came in a call from a French resident who claimed to have seen them travelling in the south of the country.

Officers believe it could be their strongest lead yet. All other reported sightings have proved to be false.

Simon Clayton left a note saying he was taking Esti on holiday

Travellers and holidaymakers are now being targeted by police in an effort to trace the father and daughter's movements.

Photographs of the pair have been made into a poster and circulated to French police stations and camp sites.

The child's mother has renewed her appeal for her safe return, but believes Esti's father may have taken her to live in France permanently.

"We need anyone who might have seen them to come forward, so that we can find Esti," said Aneta Clayton.

Appeal for help : Esti's mother Aneta

"If anyone saw Simon and Esti on a ferry, or buying petrol somewhere, please contact the police."

Esti went missing after staying with book dealer and former pilot Mr Clayton on 9 April.

He left a note for her mother, Aneta, saying he was taking their daughter on a three-week holiday.

Police officers suspect that Mr Clayton - who is from the Hay-on-Wye area - acted to avoid going through a planned court hearing over custody.

It is believed father and daughter boarded a ferry to Caen in France from Portsmouth on the day they disappeared.

Mr Clayton was due to appear at a court hearing in Brecon, at which a residence order was granted to Estelle's mother, Aneta.

Investigations have shown he had withdrawn several thousands of pounds before making the trip.

It has also been discovered that he is no longer paying the rent on his house near Hay-on-Wye and has made arrangements for his pets to be cared for.

Police checks on his computer have revealed that he had previously researched the subject of child abduction on the internet.

Officers from Dyfed-Powys Police are appealing to anyone travelling to Europe or Morocco to report any sightings of a red Volkswagen Caravelle, registration number A276 OFJ.