Shock figures show the scale of the problem of drivers using mobile phones at the wheel in Peterborough.
Cambridgeshire Police prosecuted nearly 2,500 in the city and across the county last year.
The news comes as Police and Crime Commissioner Sir Graham Bright backs calls for bigger fines.
The government wants fixed penalty fines increased from £100 to £150 and the number of penalty points drivers receive raised from three to four.
For drivers of larger vehicles such as HGVs, points would rise from three to six points.