According to witness reports, Njenga was in a convoy along the Nyahururu-Oljororok Road when men in a speeding vehicle sprayed them with bullets.
Those who died in the attack were three men and two women.
Police said two of the deceased were in the same vehicle with Njenga while three others were in a different vehicle which was also sprayed with bullets. Both drivers died during the attack that occurred at about 1 pm.
One of the women is said to have died after the vehicle lost control and rolled several times, because there was no visible bullet wound on her body, police said.
Njenga was being treated at the Nyahururu district hospital. It is understood Njenga was wearing a bullet proof vest during the attack.
Njenga who spoke to journalists from his hospital bed recalled how a vehicle tried to overtake them before its occupants opened fire.
“The vehicle was overtaking us while we suddenly saw the occupants brandishing guns and shot at us. I was shot on the hand and also a bullet cut my right finger,” he said.
Police in Nyahururu could not immediately say who the attackers were or their motive.
“We have received the reports and we are trying to establish the motive of the attack, as we look for the attackers,” a senior police officer briefed on the matter said.
Police said they will investigate to establish if the attack was in any way linked to the rivalry with other splinter groups within the criminal gang.