They immediately knelt before John Tzimiskes , Nikephoros ' murderer and hailed him as Emperor .
A servant had managed to call for the guards while the Emperor was being attacked , but when they arrived he was dead .
guards immediately knelt before John Tzimiskes , Nikephoros ' murderer and hailed him as Emperor .
A servant had managed to call for the guards while the Emperor was being attacked , but when they arrived he was dead .