Police have appealed to the public for information after two legs, believed to be those of a newborn baby, were discovered in a park in south-west London.
Officers were called to the Doctor Johnson Avenue area of Tooting Bev Common on 10 September, following reports of the discovery of human remains.
Metropolitan Police now say the legs are believed to have been severed from a newborn baby, born in the last two weeks. A post-mortem could not determine a cause of death.
A Met police spokesman added: "The baby is white but the gender has not been ascertained.
"We have serious concerns for the mother, or parents, of this child and would urge them to come forward and speak to police or seek medical aid.
"We would also like to appeal to those that work in the medical or caring professions who may have information about the possible identity of the mother or child."
A search is continuing across the area for further remains. The area where the body parts were found is about two miles from St George's Hospital in Tooting.
It is unclear how or why the body parts were dumped in the area.
Police have said no arrests have yet been made as part of the investigation.