Leviticus 5:2-3

²or if any one touch any unclean thing, whether it be the carcass of an unclean beast, or the carcass of unclean cattle, or the carcass of unclean swarming things, and be guilty, it being hidden from him that he is unclean;

³or if he touch the uncleanness of man, whatsoever his uncleanness be wherewith he is unclean, and it be hid from him; and, when he knoweth of it, be guilty;