Urgent search for baby as Constance Marten and Mark Gordon arrested

The newborn was thought to be days old when the couple disappeared in January.

The pair remain in custody and are being questioned, the Metropolitan Police told the BBC.

Police are asking local people to search for signs of the baby, including in sheds and outhouses.

In a direct appeal to the public, Det Supt Lewis Basford said the search was "now all about that baby".

"At present we are looking in the local vicinity to where the couple were arrested last night."

Constance Marten and Mark Gordon were found after a sighting by a member of the public in Brighton's Stanmer Villas area on Monday evening. The baby was not with them.

Det Supt Lewis Basford told BBC Breakfast he was concerned about the baby being exposed to the elements.

"The arrest location was close to open land and the couple were moving towards that land. We know that they travel, we know they travel long distances.

"My plea to the members of the public here in Brighton and crossing over towards Newhaven is to please be vigilant."

A helicopter was up overnight scouring a 10 mile search zone, while drones and police dogs were also deployed.

The couple left their home in Eltham, south-east London, in September, after Ms Marten first showed signs of pregnancy, and were living a nomadic lifestyle since.

They had been travelling around the UK by taxi since their car was found burning on the M61 in Bolton, Greater Manchester, on 5 January.

In the days after the breakdown, the couple appeared to be trying to avoid the police, travelling in quick succession to Liverpool, Essex and London.

CCTV sightings showed them apparently trying to hide their faces from cameras.

They were thought to be carrying a large amount of cash and to be using camping equipment to live off-grid, police said.

Investigators said they were worried the baby was being "exposed to sub-zero temperatures" and said they were "extremely concerned" for their wellbeing.

They also said there was no evidence that either Ms Marten or the baby had been assessed by medical professionals since the child's birth.

When they first disappeared, police said they were concerned that the couple seemed to be "constantly moving and awake for at least a few days - which must be especially draining on someone who had recently given birth with no medical attention".

At the end of January, detectives offered a £10,000 reward for information leading to the couple's whereabouts.

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Ms Marten, 35, is from a wealthy family and had a privileged upbringing, attending private school and living in a stately home in Dorset.

Police said she became estranged from her family after meeting Gordon while a drama student in 2016.

Gordon, a registered sex offender, was deported to Britain from the United States in 2010 after spending 20 years in prison for a rape he committed aged 14.

Ms Marten's father, Napier Marten, previously appealed to his daughter to turn herself in to the police.

"Even though we remain estranged at the moment, I stand by as I have always done, and as the family has always done, to do whatever is necessary for your safe return to us," he told the Independent.

Anyone with any information that could help with the search is being asked to call 999.

-bbc