Police are chasing person A. Person B observes this and lets person A into their home. The police knock at the door of Person B, asking to enter in order to search for person A. Person B refuses to let the police enter without a search warrant.
Assume for this question that the police has beyond reasonable doubt seen that person A has entered the property of person B. They are not searching at random.
As far as I know, normally, police need a court-issued warrant or similar to enter private property/domicile without permission of the occupant (owner/tenant). In the scenario described, do police need to wait for a search warrant? This would potentially allow person A to get away, unless police use additional resources to surround the property of person B until the search warrant is there. Person A might also use this time to hide or destroy incriminating evidence, if applicable.
Does it make a difference whether the police consider person A to be dangerous? Does it make a difference whether person A is a minor?
I'm interested in the situation in Germany in particular, but also in other places.