All the suspects who in the killing of Kabete MP George Muchai and his three aides have been arrested and the weapons used in the incident recovered from them.
Police Friday said they also recovered a pistol that was robbed from one of Muchai’s bodyguards.
The latest suspect was arrested in Ruiru Town before he led police to a house in Uthiru for the recoveries and more arrests.
The arrest brought to four, the number of those in custody over the last Saturday incident. Among those in custody is the gunman who pulled the trigger that left the four dead.
A G3 rifle with seven bullets was recovered from them. The pistol that the officers recovered, which they believe belonged to the slain officer had been defaced.
“We have all the four suspects who participated in the incident and all the guns they had. The guns include a rifle and pistols,” said acting Inspector General of police Samuel Arachi.
He said the suspects would be arraigned in court probably on Monday to face charges of robbery with violence and murder.
Arachi said they know the motive of the attack. Director of Criminal Investigations Ndegwa Muhoro said Mr Muchai and his aides were killed by bullets discharged by a G3 rifle.
“Ballistic tests showed the bullets were from a G3 rifle and we have recovered the gun. It is good,” said Muhoro.
Police believe the macabre attack was out of “a robbery that went awry”.
The development came as police were allowed to continue holding Simon Wambugu Gichamba, a suspect in the shooting dead of Muchai, his driver and his two bodyguards.
The court allowed the police to hold Mr Gichamba for 14 more days so that “he may help in tracing his accomplices” and allow police to complete investigations before formally charging him with the murder.
Other sources however said the suspect was found with a mobile phone belonging to one of the victims.
Teams of police from Nairobi continued to comb parts of Limuru, Uthiru, Kinoo, Ruiru and Kangemi since Wednesday before making the arrests.
This was after investigations indicated the gang had abandoned a car that they used in the attack in Ndeiya area four kilometres away from Kamandura where they had dropped two carjacked women who were the occupants of the vehicle.
Muchai, police constables Samuel Lekakeny Montata and Samuel Kimathi Kairingia and driver Stephen Ituu Wambugu were killed by a lone gunman at the Uhuru Highway-Kenyatta Avenue Roundabout on Saturday at about 2.50 am.
A postmortem done on the bodies on Wednesday showed they died out of profuse bleeding and all had bullet wounds in the chest and heads.
They were robbed of a pistol loaded with 15 bullets and a briefcase whose contents are yet to be known.
They were in a Toyota Fortuner when a car scratched it and stopped ahead of them blocking the way before a gunman wearing a balaclava jumped out and opened fire at the car.
Police investigations show the four were killed by gunmen who had earlier on carjacked and robbed two female motorists who were driving a Toyota Spacio in Wangige area.
The gang bundled the two into the trunk of the car before they drove to several spots including a popular club in Parklands, Kikuyu Town and Waiyaki Way before they shot at the MP and his aides.
According to the women, the gang later abandoned them in Kamandura area near Limuru from where they managed to make a report at the Tigoni police station.
Their car was abandoned at Ndeiya area. The women have since been questioned by police and released. The gang had also earlier on, on Saturday carjacked and robbed a motorist near Kangemi before attacking the women.
It was the attack on the women that helped police to track them down.
The incident shocked many and attracted condemnation.
Muchai was buried in his Kamulu home along Kangundo Road on Friday.