Article: The restrictions were tightened by the Defence of the Realm Act of August 1914, which, along with the introduction of rationing and the censorship of the press for wartime purposes, restricted pubs' opening hours to 12 noon–2:30 pm and 6:30 pm–9:30 pm. Opening for the full licensed hours was compulsory, and closing time was equally firmly enforced by the police; a landlord might lose his licence for infractions. Pubs were closed under the Act and compensation paid, for example in Pembrokeshire.

Question: What body enforced pubs' closing hours under the Defence of the Realm Act?
the police