A mother and father who went missing with their newborn baby have been found and arrested, police say, although the baby is still missing.

Sussex Police said that Constance Marten and Mark Gordon were spotted in Brighton by a member of the public just before 9.30pm on Monday.

They were arrested and are in police custody.

Their baby is still missing, however, and an urgent search operation is underway in the area, police said.

Marten, 35, and Gordon, 48, were reported missing after their car broke down near junction four of the M61, near Bolton, on Thursday 5 January.

Over the following days, there were sightings of them in a number of places, including Liverpool, Essex, south London and East Sussex.

Authorities previously believed the couple had been sleeping rough in a blue tent, and had avoided being traced by the police by moving around frequently and keeping their faces covered in CCTV images.

In the days after they went missing, Detective Superintendent Lewis Basford said the baby was “at the heart of the investigation” and that concerns were rising “day by day” for the child’s wellbeing.

Ms Marten, who is from a wealthy family, has lived an isolated life with Mr Gordon since they met in 2016.