An error has been identified in the written answer given on 05 March 2019.
The correct answer should have been:
The information requested is not collected centrally.
The Home Office collects data on the number of offences involving knives or firearms recorded by the police in England and Wales at the Police Force Area level but not at local authority level.
Information on offences involving knives / sharp instruments or firearms by Police Force Area can be found in the Offences involving the use of weapons data tables published by the Office for National Statistics, available here: