preventive detention laws has to be clearly indicated. Subsisting custody of the detenu by itself does not invalidate an order of his preventive detention, and the decision in this regard must depend on the facts of the particular case. Preventive detention being necessary to prevent the detenu from acting in any manner prejudicial to the security of the State or to the maintenance of public order or economic stability etc. ordinarily, it is not needed when the detenu is already in custody. The detaining authority must show its awareness to the fact of subsisting custody of the detenu and take that factor into account while making the order. If the detaining authority is reasonably satisfied with cogent materials that there is likelihood of his release and in view of his antecedent activities which are proximate in point of time, he must be detained in order to prevent him from indulging in such prejudicial activities, the detention order can be validly made. Where the detention order in respect of a person already in custody does not indicate that the detenu was likely to be released on bail, the order would be vitiated. (See N. Meera Rani v. Govt. of T.N. [(1989) 4 SCC 418 : 1989 SCC (Cri) 732 : AIR 1989 SC 2027] and Dharmendra Suganchand Chelawat v. Union of India [(1990) 1 SCC 746 : 1990 SCC (Cri) 249 : AIR 1990 SC 1196] .) The point was gone into detail in Kamarunnissa v. Union of India [(1991) 1 SCC 128 : 1991 SCC (Cri) 88 : AIR 1991 SC 1640] . The principles were set out as follows: even in the case of a person in custody, a detention order can be validly passed: (1) if the authority passing the order is aware of the fact that he is actually in custody; (2) if he has a reason to believe on the basis of reliable material placed before him ( a ) that there is a real possibility of his release on bail, and ( b ) that on being released, he would in all probability indulge in prejudicial activities; and (3) if it is felt essential to detain him to prevent him from so doing. If an order is passed after recording satisfaction in that regard, the order would be valid. In the case at hand the order of detention and grounds of detention show an awareness of custody and/or a possibility of release on bail.”