Missing baby in Sussex: Police helicopter, sniffer dogs, thermal imaging cameras and drones used as search continues for Constance Marten's child

With their baby still missing, Constance Marten and her partner, Mark Gordon, have been further arrested on suspicion of gross negligence manslaughter, according to the Metropolitan Police. They had been on the run for more than two months before they were found in Brighton.

The pair were arrested in Stanmer Villas at around 9.30pm on Monday (February 27) after a member of the public saw them in a shop in Hollingbury Place – but their newborn baby was not with them.

Police said officers are ‘continuing extensive searches’ for the missing infant. More than 200 officers from multiple units in the Met and Sussex are involved in the search.

Chief Superintendent James Collis, from Sussex Police, said: “We are supporting the Metropolitan Police on this extensive search. Thanks to the vigilance of a member of the public, our officers were on scene within minutes of the reported sighting and made arrests.

“An immediate search was launched including the National Police Air Service helicopter, drones, dog units, and every available officer and staff member from across the force.

“These searches are ongoing and the public can expect to see an increased police presence in the area, as well as a dedicated response to any information from the public."

The pair were initially arrested on suspicion of child neglect, police said. Marten and Gordon remain in custody however the Met are yet to gain any further information which will help locate the baby

"They were later further arrested on suspicion of gross negligence manslaughter,” a Met Police spokesperson added. “They remain in custody at a police station in Sussex.”

Detective Superintendent Lewis Basford, of the Met, said that – while there was still hope to find the baby – the risk is ‘extremely high’ and is increasing each hour, ‘particularly with the declining weather conditions’. This is being reviewed hour by hour, he said.

The DS said the key priority of the Met has been finding the baby ‘and we remain committed to that’.

He added: “There is a significant amount of police search activity in open spaces to the north of Brighton near to where the couple were arrested last night.

"Before the arrest, the last known sighting of the couple was in Newhaven on Wednesday, January 8. I'm therefore appealing to members of the public between Brighton and Newhaven to report any potential sightings, or information about where they may have been sleeping.

"I’d also ask people living in these areas to report any suspicious behaviour or items found in their gardens, outbuildings and sheds, between then and now.

“Equally if you are out walking in these areas and you discover something you think we should know about, please don’t hesitate to contact us, no matter how insignificant it may seem. Support from the public is vital and we ask people to remain vigilant.”

Detective Superintendent Basford said officers have received a ‘large number of phone calls’ from members of the public during the investigation.

"I would like to thank everyone who has come forward with information to assist us, and especially the person who quickly called police last night after spotting Constance and Mark,” he said.

"Our colleagues from Sussex Police were on the scene within minutes to make the arrest. We are very grateful for the support they are providing.

“Anyone with any sightings or information that could assist the search is asked to call the incident room on 0208 3453 865 or 999 with anything they believe may be significant.”

Chief Superintendent Collis said there may be disruption to people living and working in the Brighton area, ‘and we thank people for their patience and understanding at this time’

“I’d like to further thank the local community for all the help they’ve given us so far,” he said. “We have an extensive search area and will be in the community for some time.

“Some people want to know how they can help – we just ask you to remain vigilant, and please report anything of note to us.

“If you have any information that will support the search, please call 101. In an emergency, please dial 999. We have dedicated call handlers available to talk with you.”

The Met said earlier today that it was still continuing to offer a reward of up to £10,000 for any information that leads to the baby being found.