Unknown people have torched the offices of Homa Bay Governor Cyprian Awiti, reducing to ashes crucial documents.
They set on fire the building situated in Homa Bay town Thursday night and it was still burning by Friday morning.
Homa Bay County Police Commander Marius Tum said one person has been following the incident.
He has said the person is not a resident of the county but was arrested at the scene with burns and petrol suspected to have been used to start the fire.
The police boss said officers were at the scene to investigate the attack with a view to arresting the culprits behind the arson attack.
Affected offices include procurement and all finance departments.
On Tuesday, detectives from the Ethics and Anti-Corruption Commission (EACC) had raided the same offices and confiscated a set of documents and computers.
An EACC official who sought anonymity had told Nation that they conducted the raid over the possible loss of Sh5 billion from imprest accounts of senior county government officials.