There was panic when a man attacked and killed an armed police officer manning State House, Nairobi.
The motive was not immediately known.
The General Service Unit officer was speared in the chest by a 56-year-old man who was arrested at the scene.
The assailant used a spear to commit the murder outside Gate D that is usually used by the public to access the State House.
The officer was on duty at the time of the incident with other colleagues when he was attacked.
The motive of the Monday morning incident was not immediately established.
The officer attached to the General Service Unit’s G Company was pronounced dead on arrival at the Kenyatta National Hospital.
He had bled profusely by the time he arrived at the hospital, officials said.
The assailant was arrested at the scene and taken for grilling amid panic.
It is not clear if the assailant knew the slain officer. He told police he was sent by satan to kill the officer.
Witnesses said he walked to the scene posing as a member of the street families and carrying a sack.
He had stuffed the spear in the sack.
On arrival at the scene, he hid behind a flower bed and removed it before spearing the slain officer in the chest, other police officers said.