You can make an application to the police on your own behalf, or on the behalf of someone else like a friend, relative or neighbour that you think is at risk.
How to make an application. You can do this by contacting the police to log the request for a disclosure. Find your nearest police station using this link to submit a request online or visit in person. https://www.police.uk/pu/find-a-police-force/
This will then be picked up and dealt with according to the police. The police will contact the person making the request to further discuss the concerns and decide whether it is appropriate for any additional information to be shared in order to help protect the person who is in the relationship with the individual who may be at risk.