According to witness accounts, the raiders were unusually quiet thus making it difficult to determine their exact number.
At the time of the attack, Mr Ranguma — who now serves as Chairman of the Sacco Societies Regulatory Authority (Sasra) — was in Nairobi.
A gang of livestock thieves raided the rural home of former Kisumu Governor Jack Ranguma in Songhor, Chemelil, on Monday night and stole 20 sheep in a well-coordinated operation.
The incident happened around 10.30pm when the assailants accessed the property, locked the workers inside their quarters and then broke into the livestock shed.