The remains of a baby have been found in the search for aristocrat Constance Marten and Mark Gordon missing two-month-old.
Since the couple were arrested on Monday, more than 200 police officers have been engaged in the search for the two-month-old between Newhaven and Brighton.
The infant had not received any medical care since his birth in January.
Marten, 38, and Gordon, 48, refused to tell police where the infant was, sparking the massive hunt.
Detective Superintendent Lewis Basford from the Metropolitan Police, who led the investigation, told reporters on Wednesday that remains had been found in a wooded area.
The couple were initially arrested on suspicion of child neglect, and later on suspicion of gross negligence manslaughter.
The couple remain in custody after police were granted a 36-hour custody extension by Brighton magistrates.
Speaking to reporters at Sussex Police headquarters on Wednesday evening, Mr Basford said: “It is my very sad duty to update this afternoon, police officers searching a wooded area close to where Constance and Mark Gordon were arrested discovered the remains of a baby.
“A post-mortem examination will be held in due course.
“A crime scene is in place and work at the location is expected to continue for some time.
“This is an outcome that myself and that many officers who have been part of this search had hoped would not happen.
“I recognise the impact this news will have on many people who have been following this story closely and can assure them that we will do everything we possibly can to establish what has happened.”
The couple have been travelling around the UK by taxi since their car was found burning on the M61 in Bolton, Greater Manchester, on January 5.
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.
Marten, who is from a wealthy aristocratic family, was a drama student when she met Gordon in 2016.
Since then the couple have led an isolated life, and in September, as Marten’s pregnancy progressed, began moving around rental flats.
Gordon served 20 years in prison in the US for rape and battery committed when he was 14.
It is unknown if their baby was full-term or has any health issues.
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