Criminal Route with the Police

The most likely thing to do is report it to the Police. They will then take it up and proceed against the perpetrators on the complaint's behalf, giving the complaint a crime number and then the complainant advises their insurers. Some time later the bad guys are caught, sentenced and the complainant gets their money back. Well that is a lovely ideal, but it may not work like that.

What will typically happen is that the Police will attend the scene, take notes and statements and investigate the crime.

Once they have enough evidence collected they send the case to the Crown Prosecution Service who is the principle public prosecuting service for England and Wales

The CPS Process
General Principles
The Decision to Prosecute
Review
The Full Code Test
The Threshold Test