Police revealed that a primary suspect in the murder of Wells Fargo HR manager Willis Ayieko, identified as Robert Wakolo Okoth, had a history of violent crimes, including the fatal shooting of Mpesa agent Grace Awino in Kisumu on January 27, 2024. Okoth, who went by multiple aliases, was confirmed by his father and identified via an ID from a police database. After evading police, he was fatally shot in a Kisumu hideout. A firearm was retrieved, and further investigations linked him to past robberies where AK-47 rifles and other stolen items were recovered.