The gunmen who attacked National Super Alliance (NASA) leader Kalonzo Musyoka’s Karen home used a stun hand grenade to execute their mission.
They also shot twice in the air before escaping from the heavily secured area.
But the motive of the attack remains a mystery. Police confirmed they had recovered a safety pin pulled from the grenade and one live bullet used in AK-47 rifles.
Police spokesman Charles Owino, who accompanied detectives from Nairobi Area command and the Bomb and Hazadrous Disposal Unit of the Directorate of Criminal Investigations (DCI) to the scene, confirmed the attackers used a bomb usually used to scare rather than harm.
Nairobi’s head of DCI Nicholas Kamwende and the head of the Bomb Disposal Unit, Eliud Lagat, were at the scene.
A stun grenade, also known as a flash grenade or a thunder flash, is a device used to produce a loud sound, but has no shrapnel that can hurt.
“We have located where it landed and recovered a safety pin the was removed from the stun grenade. We also recovered a live bullet from the scene,” said Mr Owino.
He said the detectives want to establish the source of the weapons, commonly used by security agencies, including wildlife officials, to scare animals in forests.
The incident happened around 1am yesterday. By then, Kalonzo, who is a former vice president, and his family were at home asleep.
His personal assistant identified only as Matiki said the attackers arrived in two saloon cars and drove past the main gate after realising there were private guards on duty.
“They made a U-turn metres ahead and stopped opposite another gate, hurled the grenade into the compound before shooting at least two times,” said Matiki.
He said the attackers drove off soon after the incident. This was after the sound of the grenade and shots alerted two Administration Police officers manning a private home opposite Kalonzo's.
“The officers cocked their guns from their sentry post, alerting the gunmen who jumped back into their cars and drove off,” he added.
Kalonzo is a neighbour of Deputy President William Ruto among other prominent personalities in the area.
He kept the bullet and safety pin until morning, when he handed them to the police.
The Scenes of Crime officers collected other samples and left, saying they would be analysed to establish the manufacturers.
The incident came hours after security seconded to Kalonzo and other NASA principals was withdrawn without explanation.
The withdrawal happened ahead of the planned 'swearing-in' of Raila Odinga and Kalonzo as 'people’s president' and 'deputy president' on Tuesday.
Kalonzo hired private guards to man his gate and compound.
Yesterday, a group of politicians who visited his home condemned the withdrawal of security, terming it intimidation.
Senate Leader of Minority Moses Wetang’ula said the attack was an attempted assassination.
"The protection of leaders and Kenyans at large is the duty of the Government. The NASA leadership is exposed by the withdrawal of our security. The law doesn’t allow us to get private and armed security,” said Mr Wetang’ula.
He also termed the attack beastly, adding it was aimed to harm Kalonzo and his family.
Makueni MP Dan Maanzo said such weapons belonged to the Government, adding the Jubilee administration should accommodate divergent views.