The deceased infant was found at the site in Cambridge just before midday on Tuesday, and police have appealed for the mother to come forward.

"This is an incredibly sad and upsetting incident for everyone involved and we are in the process of trying to establish more details," Detective Superintendent John Massey said.

He added that officers are trying their "hardest to get to the bottom" of what happened at the plant in Ely Road, Waterbeach, calling for anyone with information to get in touch.

In a direct appeal to the baby boy's mother, he said: "It may be she needs medical care or is in a vulnerable situation."

"Any information, no matter how small, could help the investigation run by our specialist child safeguarding team."