The firearms used by suspects who carjacked the driver of Secretary to the Cabinet Francis Kimemia are commonly used by police.
Investigations now seek to establish if the attackers were police officers.
Detectives found spent cartridges of a G3 rifle, a Ceska pistol and a revolver. Also found in the car were three mobile phones.
Nairobi County police commander Benson Kibue on Monday said that all the bullet heads and spent cartridges had been taken for ballistic examination to establish if they belonged to police.
Mr Kimemia’s driver had just dropped him off at his residence in Kileleshwa before driving to Pangani where he was taking his other colleague.
The car was hit from behind by another vehicle and the driver had stopped to check the extent of the damage when four gunmen attacked him and forced him to take them to Mr Kimemia’s residence.
Before heading there, they went through Gachie in Kiambu County, where the gangsters robbed motorists as they moved.
When the gangsters attempted to force their way into Mr Kimemia’s compound, police officers manning the home opened fire damaging the car before the gang of three fled with the driver still on board during the 3am incident.
The driver was slightly injured after he disembarked from the moving car as Mr Kimemia’s security engaged the gangsters.
Bloodstains were found on the driver’s seat, with police reporting they had shot one of the gangsters.
The car was found abandoned at Gatina area in Kawangware.-nation.co.ke