Therefore, necessary steps should be taken to prevent these incidents without any loss of time, it added.
A detailed report should be sent to the Ministry of Home Affairs (MHA) immediately, it said.
In case the report is not sent by the state government, the matter will be taken seriously, the letter added.
After the third straight convincing victory for the ruling Trinamool Congress (TMC), led by Chief Minister Mamata Banerjee, following a charged Assembly election campaign, West Bengal witnessed a number of violent incidents since Sunday, when the results were announced.
At least six people were killed in post-poll violence in different parts of the state till Tuesday.