Officers from the Flying Squad on Monday afternoon raided the home of billionaire businessman Jimmy Wanjigi in Nairobi.
The officers conducted the raid at Wanjigi's residence located opposite to that of US ambassador to Kenya Robert Godec in the upscale Nairobi's Muthaiga estate.
The operation comes after detectives nabbed five AK47 guns and hundreds rounds of ammunition at another house in Malindi, Kilifi county believed to be owned by the controversial tycoon.
Four employees working for Wanjigi were taken in for grilling by detectives.
A similar raid was carried out at the Muthaiga residence by officers attached to the Special Crimes Prevention Unit on Monday afternoon.
Neither the businessman nor police have issued a formal statement regarding the whole incident.
Wanjigi is said to be one of the main financier of opposition National Super Alliance (NASA) presidential candidate Raila Odinga's August 8th election campaigns.