HNJ 667D A 1966 DMW Deemster. A small fleet of such motorbikes were built in Wolverhampton using Villers 250 cc engines. They were used by Sussex Police in the Lewes area. Notice that the bike carries a front registration plate and only has headlights to the front. Arm signals were used in place of indicators.
A look at the bike from the side. It is now in private ownership by one of the mechanics who originally built it.
The spartan controls show a telephone handset for contacting the control room and two circular duckets for storage.