Site of interest ruled out during search for mother and newborn after placenta found on Cooks River

New interesting site to search for missing baby and mother in the suburbs Sydney a false alarm has been reported.

It’s been more than 24 hours since a dog walker discovered a human placenta and umbilical cord near the Cooks River in Earlwood on Monday afternoon.

WATCH VIDEO ABOVE: Desperate search for missing mother and baby

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Around 10 a.m. Tuesday, police identify a new site of interest near the riverbank and covered it with a blue tarp while investigators looked into the possibility of buried material there

Instead, police found a freshly buried cat at the site.

The search is therefore continuing with forensic tests to establish when and where the birth took place, with detectives unable to rule out the possibility that the unidentified mother gave birth to her baby on the banks of the notoriously polluted river.

One line of inquiry is whether the newborn, along with other evidence of the birth, was dumped, although police have yet to find anything to indicate the baby was harmed.

Police divers and a blood-sniffing dog were called in on Tuesday morning as part of the ongoing massive search, but the operation was over by early afternoon.

The site where the placenta and cord were found is not far from a sports field and Islamic center on Lang Rd, which ends with a busy footbridge over the river.

An “obvious” discovery

Tony Robson and his wife came across the organ “sitting on the mud” at low tide while walking their two dogs.

“We left the boys (dogs) as it is a secluded cul-de-sac. The boys were off the lead and wandering around a bit and Barry (the white dog) jumped down into the mangroves and spotted something,” Robson told 7NEWS.

“He was acting a little strange, so we looked down and found this … human placenta with an umbilical cord attached.”

Robson was at the birth of her three children and said it was “obvious” what it was.

“I couldn’t think what else it could be … my wife took a picture of it and we called the police,” he said.

Chief Christine MacDonald said the police’s main focus is the welfare of the woman and her child.

“Birth, for many people, can be a traumatic time and it can be very distressing… I am deeply concerned about the safety and mental health of the mother,” she told reporters on Tuesday.

The woman may have given birth and thrown the placenta and umbilical cord into the river because she didn’t want anyone to know about the baby, McDonald said.

“There is no judgment, they need to know that we are concerned about 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 south-west Sydney and empties into Botany Bay at Keemagh, 23 kilometers away.

The sites are heavily polluted as a result of traffic jams, waste, sewage, illegal dumping and industrial and domestic activities.