Yes, I know that he can be put to death according to Islam, because according to the nature of crime the punishment is meted out, they have a relationship. So if anybody has taken life without having any right he forfeits his own right to live. It is as simple as that. But in Islam there is a provision for the relatives of the murdered to come to an understanding, to get some ransom money or something and then to forgive him.
But the right of forgiveness lies with the descendants or other very close blood relations of the person who has been murdered. The state cannot pardon him on its own. As far as the state goes, the punishment is death for the murderer. That is what you wanted to find out? Just any form, hanging is not prescribed in Islam. It is not necessary, beheading or hanging, just death. That’s all.