The plot to shoot and kill former Garissa Finance chief Idris Mukhtar was hatched in May, a source close to the investigation has said.
Investigations led to the questioning of Garissa Governor Ali Korane on Tuesday.
Korane recorded statements with Kilimani police on Tuesday evening. He was picked up at his Kilimani home and questioned until 9pm when he was released.
Kilimani DCI Fatuma Hadi asked Korane to take his original academic papers to the station yesterday. The governor did not deliver the papers.
The planners first mooted the idea in May at locations in Nairobi.
Mukhtar was shot once in the head on August 20 by gunmen, while leaving a mosque in Kileleshwa, Nairobi. He is fighting for his life at Nairobi Hospital.
A close relative of Governor Korane met three suspects, all men, believed to be the hired assassins from Dandora at different Nairobi eateries to plan the execution.
Police said the hired killers were promised Sh1.8 million by Korane’s relative accused of masterminding and financing the operation.
The planners wanted Mukhtar and Nairobi lawyer Charles Kanjama eliminated after they learnt of a plan by the two to challenge Governor Korane’s academic qualifications in court.
In February, the University of Nairobi disowned a master’s degree that Korane claimed to have been awarded by the institution in 2011.
In a letter to Musyoka Murambi & Associates dated January 30, the university said Korane did not graduate there. This put the county boss under the radar of the EACC.
One of the men arrested in connection with the shooting is said to have confessed to the police.
Such a confession is not admissible in law and police have decided to only use the information to advance their investigations.
Yesterday, a man said to be the brother of the governor was arrested in Nairobi. Bunow Korane, was arrested outside a shopping mall on Kimathi Street by officers from the Flying Squad.
There was drama as Bunow attempted to flee from the officers. He was overpowered and bundled into a waiting police car. He was handed over to Kilimani DCI officers for questioning.
Nairobi DCI chief Ireri Kamwende confirmed the arrest but declined to comment further.
Sources familiar with the investigations said police yesterday analysed a third mobile phone recovered from the governor’s home on Tuesday night. Yesterday’s arrest on Bunow brings to eight the number of suspects arrested by the police in connection with the shooting of Mukhtar.
Police on Tuesday recovered a vehicle believed to have been used by the shooters. The vehicle was traced to a garage in Ngara, where it was being repainted from grey to red.