X, a jailor, has the charge of Z, a prisoner. X, intending to cause Z's death, illegally omits to supply Z with food; in consequence of which Z is much reduced in strength, but the starvation is not sufficient to cause his death. X is dismissed from his office, and Y succeeds him. Y, without collusion or co-operation with X, illegally omits to supply Z with food, knowing that he is likely thereby to cause Z's death. Z dies of hunger. What will be position under Indian Penal Code, 1860?