Related Rule
India
Practice Relating to Rule 99. Deprivation of Liberty
Section C. Prompt information on the reasons for deprivation of liberty
India’s Police Manual (1986) states that the reasons for a detention order should be communicated as soon as possible, but ordinarily not later than five days after arrest, and in exceptional circumstances, for reasons to be recorded in writing, not later than ten days. For Punjab and Chandigarh, this period was extended to 15 days. 
India, Police Manual for Handling Civil Disturbances, Home Ministry, Government of Maharashtra, Bombay, 1986, pp. 21, 27 and 29.
Countless pieces of domestic legislation provide for prompt information of the reasons of detention. For instance, preventive detention is permitted by India’s Constitution (1950) subject to a number of safeguards, namely that detainees have a right to be informed of the reasons for the detention order. 
India, Constitution, 1950, Article 22.