Section 755(a) in Police Regulations, Bengal , 1943
(a)Under the provisions of the Regulations for the Army in India, there is no objection to the employment of reservists of the Indian Army in the Bengal Police Force. They may be recruited up to a limit of not more than 10 per cent, of the strength of a district without the consent of the Deputy Inspector-General, and not more than 12V& per cent, of the strength of a Range without the consent of the Inspector-General, subject to the following conditions :-(i)they must be fully trained in drill and fire a musketry course each year (with the police), and(ii)they must be released from their employment immediately mobilization is ordered to enable them to rejoin the colours.