Detectives investigating the death of a baby found in a brook are appealing for a girl seen pushing a pram close to the area to come forward.
The baby's body was found in a stream in Kirkham, Lancashire, on Saturday by a dog walker.
Police said on Tuesday that they now have information relating to a girl in her late teens being spotted on a dirt track near Carr Lane, close to the scene, pushing an empty pushchair.
The teenager was seen at around 7pm on Monday September 26 or Tuesday September 27, police said.
The girl was said to be 5ft 5in, with dark hair pulled into a ponytail and wearing dark trousers and a zip up top.
Senior investigating officer Detective Superintendent Neil Esseen said: "This information is new and I would appeal for that person to come forward so they can be ruled out of the inquiry.
"I would also extend that appeal to the Kirkham community and ask them to think back and see if they can remember witnessing a girl pushing a pram. Even the smallest pieces of information may prove crucial in finding out exactly what has happened."
Police said they have not ruled out foul play as the death remains unexplained but it is more likely a case of child abandonment
Officers have also released photographs of items found at the scene close to the body.
They include two towels, one with the Union flag on and one green, and a brown fleece - which the child was wearing - that was originally blue and white and from Asda.