A new site of interest in the search for a missing baby and mother in suburban Sydney has been declared a false alarm.
It has been more than 24 hours since a dog walker discovered a human placenta and umbilical cord near the Cooks River at Earlwood on Monday afternoon.
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About 10am on Tuesday, police identified a new site of interest near the river bank and covered it with a blue tarpaulin as investigators looked at the possibility material had been buried there
However, police instead discovered a freshly buried cat at the location.
The search therefore continues with forensic testing underway to probe when and where the birth took place, with detectives unable to rule out the possibility the unidentified mother delivered her baby at the side of the notoriously polluted river.
One line of inquiry is whether the newborn, along with other evidence of the birth, was dumped, although police are yet to find anything to indicate the baby had been harmed.
Police divers and a blood-detection dog were called in on Tuesday morning as part of an ongoing, large-scale search, but the operation was winding down by early in the afternoon.
The site where the placenta and cord were found is not far from a sports field and an Islamic centre on Lang Rd, which ends with a busy footbridge across the river.
‘Obvious’ discovery
Tony Robson and his wife came across the organ “sitting on top of the mud” during low tide as they walked their two dogs.
“We let the boys (dogs) off as it’s a secluded dead-end spot. The boys were off-lead having a bit of a romp around and Barry (white dog) jumped down into the mangroves and spotted something,” Robson told 7NEWS.
“He was acting a bit weirdly so we looked down and found this … human placenta with an umbilical cord attached.”
Robson was at the birth of his three children and said it was “obvious” what it was.
“I couldn’t think what else it could be… my wife took a photo of it, and we called the police,” he said.
Superintendent Christine McDonald said the main focus of police was the welfare of the woman and her child.
“Childbirth, for many people, can be a traumatic time, and it can be very distressing … I am deeply concerned for the safety and the mental health of the mother,” she told reporters on Tuesday.
The woman might have given birth and disposed of the placenta and umbilical cord in the river because she did not want anyone to know about the baby, McDonald said.
“There is no judgement, they need to know we are concerned for them,” she said.
The riverside site is less than 4km from Canterbury Hospital and is frequented by walkers, joggers and dog walkers.
The Cooks River flows from Yagoona in Sydney’s outer southwest and runs into Botany Bay at Kyeemagh, 23km away.
Sections are heavily polluted as a result of traffic congestion, litter, sewage, illegal dumping and industrial and domestic activities.