Police said a newborn baby found dead outside a church in west London was discovered in a black M&S bag with pictures of avocado on the side.
The Metropolitan Police said officers and the ambulance service were called to the end of Talbot Road, in Notting Hill, at 12.46pm on Tuesday.
The baby boy, who was found outside All Saints’ Church, was declared dead at the scene.
Superintendent Owen Renowden described the case as “shocking and tragic” as he gave an update on Wednesday morning.
He said they were “really worried” about the mother’s wellbeing “as she will have recently given birth”.
Spt Renowden went on: “I know she will likely be feeling very frightened and going through an extremely difficult time.
“If you are the baby’s mother and you see this today, I want to appeal directly to you to come forward and receive help, my priority is to help you, to make sure that you can receive medical assistance.”
He added she can get assistance at anytime by attending any hospital, police station or by calling the emergency services.
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He also appealed to anyone who may have information that can assist with police inquiries.
Anyone with information should call 101 or make an online report quoting reference 1879 and today’s (26/3) date.