Is your partner on the birth certificate?
You need to get legal advice ASAP.
There are two divisions of family law, the one that deals with care orders, social services and the like and the other one which deals with disagreements within the family.
Your posts make it sound as if you are going to be dealing with the second kind.
Social services do not always help with these type of cases as they are seen as private family law matters.
Basically in their eyes, there is a disagreement between the two parents over who should look after the baby, the mother or the father?
The only way I can see the Police being able to help you is if the father DOES NOT have parental responsibility (PR) for the baby.
If you are unmarried but the father is on the birth certificate then he has PR and in the eyes of the law, he has every right to keep the baby until there is a court hearing.
Tell me, is the father on the birth certificate?