A woman has told how she heard Constance Marten and Mark Gordon having a blazing row minutes before police swooped to arrest them.
The arguing couple were caught on doorbell footage bickering at Stanmer Villas, Brighton, moments before officers finally caught up with the couple.
As 200 police continue to comb Sussex looking for their missing newborn baby, they were this afternoon re-arrested on suspicion of gross negligence manslaughter.
Moments after they were recording rowing, they were taken into custody on suspicion of child neglect.
Constance was reportedly tearful when officers took them in, yelling at officers to 'get off' her boyfriend when he was restrained.
A witness claimed it took police 40 minutes to subdue him as they struggled to arrest the 48-year-old.
Ms Marten, 35, was carrying a bag of shopping in the footage.
The couple had reportedly been sleeping rough before they were eventually found, having been missing for 53 days.
Speaking in Brighton, detective superintendent Lewis Basford said that the risk to the couple’s missing baby was getting “so great” that officers “have to consider the baby has come to harm”.
He added that the couple were still refusing to tell cops where the child is - or even the sex of the baby.
The woman who handed MailOnline the footage asked to remain anonymous, but said they seemed 'angry'.
"They were talking loudly, that's what got my attention - I've never seen them around here before, they were wearing a lot of layers as it was cold," she said.
"I couldn't tell what they were saying but the man seemed to me to be slightly angry. They'd been to the shops around the corner and were heading back somewhere. They were both carrying bags filled with food.
Hope is fading fast for the child as a huge search in Sussex continues tonight.
The pair, who had been missing since early January, were avoiding police since the infant was born in early January, moving around the country, paying for everything in cash and covering their faces when on CCTV.
Detective Superintendent Lewis Basford told reporters today: "I can confirm that they were initially arrested on suspicion of child neglect.
"I can now confirm that they have been further arrested on suspicion of gross negligence manslaughter. They remain in custody at police stations in Sussex.
"The baby was not with them, and we have not found the baby yet."
Following the arrests, Constance's father Napier Marten said he was "very alarmed" that the baby remained missing.
He said that he loves his daughter dearly, but it would have been "far better" if she and Gordon handed themselves in earlier.
Mr Napier told The Independent: For whatever reasons she and her partner went on the run, the consequences of their actions have increased many fold. It would have been far better if they had handed themselves in earlier."
He thanked the member of the public who tipped off police about the couple's whereabouts, as well as Metropolitan police officers for their "dogged investigation".
Anyone who may be able to assist in the search for the couple's baby is urged to contact 999.