It is a law enforcement phrase meaning forcibly entering another's premises. It is about the same as 'burglary', but no further crime is intended.
breaking and entering
n. 1) the criminal act of entering a residence or other enclosed property through the slightest amount of force (even pushing open a door), without authorization. If there is intent to commit a crime, this is burglary. If there is no such intent, the breaking and entering alone is probably at least illegal trespass, which is a misdemeanor crime. 2) the criminal charge for the above.
burglary
n. the crime of breaking and entering into a structure for the purpose of committing a crime. No great force is needed (pushing open a door or slipping through an open window is sufficient) if the entry is unauthorized. Contrary to common belief, a burglary is not necessarily for theft. It can apply to any crime, such as assault or sexual harassment, whether the intended criminal act is committed or not. Originally under English common law burglary was limited to entry in residences at night, but it has been expanded to all criminal entries into any building, or even into a vehicle.