Police searching for the missing child of Constance Martin and Mark Gordon have found the remains of a child.
The discovery was made in an area of woodland as hundreds of officers and volunteers searched the 90 square mile area near Brighton.
The pair went missing in early January and were arrested earlier this week.
They are being arrested on suspicion of murder with gross negligence.
Metropolitan Police Deputy Superintendent Louise Basford, who is leading the investigation, said the body of a child was found close to where the couple were arrested on Monday.
“This is an outcome that I, and many of the officers who have been a part of this search, hoped would not happen,” he said.
“I know this news will have an impact on many people who have been following this story closely and can assure them that we will do everything possible to establish what happened.”
He said a post-mortem examination would now be carried out to help detectives as they try to figure out what happened. Earlier, the police had been given an additional 36 hours to interrogate the couple.
Teams continue to comb the area by flashlight for evidence, the final phase of a 55-day search that ended in tragedy.
A missing persons investigation surrounding Ms Martin and Gordon – a convicted rapist and registered sex offender – began after their car was found crashed near Bolton on January 5.
This triggered a national search and sightings were reported in Liverpool, Essex and London, mostly limited to brief snippets of CCTV footage.
Police believe they were sleeping outside in a tent and living off the grid, raising fears for the child’s health in the winter temperatures.
The last confirmed sighting of the couple before their arrest was on January 8 in New Haven. Police had earlier said that her child was with her at the time and was alive.
