How Constance Marten and Mark Gordon were caught: A chance encounter outside a corner shop

Police swooped in six minutes after a member of the public recognised the couple’s faces from news

Fifty-three days after going on the run with a newborn baby, missing aristocrat Constance Marten and her boyfriend Mark Gordon were finally caught – with help from a member of the public outside a corner shop.

The couple were recognised by a passer-by thanks to media appeals, and police swooped just six minutes later as they walked up a nearby Brighton street.

“Just after 9.30pm, yesterday [Monday] evening a member of the public – off the back of media reporting of images of the couple – sighted them outside of the Mulberrys convenience store on Hollingbury Place,” Detective Superintendent Lewis Basford told a press conference.

“They saw the couple withdrawing cash and dialled 999. The time between that call being registered and police arriving at the scene was six minutes.”

He described Ms Marten and Gordon as “heavily clothed for outdoor activity” and said they underwent medical checks in custody after being arrested on suspicion of child neglect.

It had been over seven weeks since the last confirmed sighting of the pair, who were caught on CCTV around 10 miles away in Newhaven on 8 January.

Police believe they had been sleeping rough and walking long distances on foot, potentially through rural areas of the South Downs, to avoid detection.

With Ms Marten and Gordon now in custody, an intense search involving 200 officers is underway for their missing baby, amid concerns for the infant’s welfare in freezing temperatures.

The senior investigating officer, Det Supt Basford, told the press conference the couple had gone to “great lengths” to hide Ms Marten’s pregnancy and avoid her giving birth under the care of health authorities.

He said that after going on the run, the newborn baby had been hidden from sight inside Ms Marten’s coat, and that taxi drivers had only been able to see the shape of the infant moving and hear it crying during journeys early in January.

Det Supt Basford said he had been concerned about the couple’s behaviour “in terms of movement [around the UK] and avoidance”.

The couple have been on the run since 5 January (Metropolitan Police/AP)

He said they had not given any information during police interviews to indicate where their baby is, if they are well or even the child’s gender.

“While there is still hope to find the baby we are continuing as time passes to be against the clock in terms of the risk posed with the climate, the weather conditions and the freezing temperatures we have had overnight,” the officer added.

“We are actively still engaged in an open land search to find the baby … whilst we’re still in the position that we hold hope the baby is safe, the risk is extremely high.”

As well as combing allotments and green areas near where the couple were arrested on Monday night, police are conducting house-to-house enquiries and trawling CCTV.

Officers are appealing for people to be vigilant in areas of the South Downs between Newhaven and Brighton, where the couple may have travelled on foot, for any sign of their blue tent or any signs that outbuildings they may have been used as shelter.

Ms Marten, 35, and Gordon, 48, have been avoiding police since the baby was born in early January, moving around the country, paying for everything in cash and covering their faces when on CCTV.

Police searched allotments near where the couple were arrested on Monday (PA)

The investigation started after their car was found on fire and abandoned on the hard shoulder of the M61 in Bolton, and a family were seen walking away on 5 January.

The following day, they took a taxi to Liverpool and then onto Harwich, Essex, where they were seen by a member of the public at around 9am on 7 January.

But by that afternoon, they were in London, being caught on CCTV near East Ham and shopping in Whitechapel Argos, where Gordon purchased camping equipment including sleeping bags and a two-person tent.

At that point they were carrying a baby buggy, but dumped it near Brick Lane before taking taxis to north London and then onwards to Newhaven.

They arrived at the East Sussex ferry port shortly before 5am and were tracked walking to an overpass, before disappearing with their tent and bags into the fields beyond.

Police said they had not yet recovered the couple’s tent or other belongings, and are continuing to offer a £10,000 reward for information.

Asked whether they may have given the baby to someone else to look after, Det Supt Basford said the “main line of enquiry” remained that they had stayed with the child.

Police searching for Constance Marten’s missing baby in Golf Drive, Brighton (PA)

“At no point have we seen in the short period of CCTV we have that they allowed others to have the baby,” he added.

“The rationale for the reward is because we cannot rule out that along that journey they have taken they have found someone who is likeminded or does not conform to the law enforcement aims of trying to protect that baby, and may have used the cash reserves we know they had to offer it for safe lodging.”

Ms Marten, who is from a wealthy aristocratic family, was a promising drama student when she first met Gordon in 2016.

Since then the couple have led an isolated life, and in September, as Ms Marten’s pregnancy progressed, began moving around rental flats.

Her father, Napier Marten, told The Independent that “whatever the weather, I love her dearly and will support her best I can”.

“It is an immense relief to know my beloved daughter Constance has been found, tempered by the very alarming news her baby has yet to be found,” he added.

“For whatever reasons she and her partner went on the run, the consequences of their actions have increased manyfold. It would have been far better if they had handed themselves in earlier.”