"The Prophet (may Allah's peace and blessings be upon him) announced the death of the Negus on the day he had died. He took the people to the prayer place, lined them up, and made four Takbīrs." [Al-Bukhari]

عن أبي هريرة -- قال: «نَعَى النبيُّ -صلى الله عليه وسلم- النَّجَاشِيَّ في اليوم الذي مات فيه، خرج بهم إلى المصلَّى، فصفَّ بهم، وكَبَّرَ أَرْبَعاً». (البخاري)