The officer, who is said to have been radicalized by the dreaded Al Shabaab terrorists group, reportedly was on a mission to attack the GSU Recce squad headquarters based in Ruiru.
Police officers, attached to the Ruiru police division, raided a house belonging to the suspect but did not find him.
The officers only found literature linking him to the dreaded terror group.
"We only found literature material that suggested that the man was radicalised," a senior police officer was quoted as saying.
The suspect Constable Eric Ngethe-No 97861-is said to have been spotted at the Riyadh Mosque which is associated with radicalization.