Three suspected highway robbers, among them a woman, were on Saturday night gunned down at Mithuri in Naivasha by police officers.
Naivasha deputy OCS John Kwasa told Nation the suspects were shot and killed after they defied orders to surrender.
Mr Kasa said the trio were in a gang of six that was planning to hijack a Nairobi-bound bus when they were ambushed by his team acting on a tip-off.
"We have launched a manhunt for the other three who escaped with gunshot wounds," said Mr Kwasa.
Police recovered a homemade gun, machete, 10 mobile phones, SIM cards, clothes and other items from the slain suspects.
Mr Kwasa linked the suspects to a series of hijacking incidents on the Nairobi-Nakuru and Maai Mahiu-Narok highways.
In the wee hours of Saturday, Mr Kwasa said the gang hijacked a Narok-bound matatu and robbed passengers of their personal belongings.
"Some of the recovered items were stolen from passengers travelling in the matatu that was hijacked in the morning," he said.
The gang is said to have also hijacked a Nairobi bound vehicles on Wednesday and Thursday.
A detective, who had been trailing the gang, said the slain woman was the ringleader.
"In all the cases that I have been tasked to investigate, the victims have been narrating about a ruthless, middle-aged woman with an elaborate tattoo on her left hand," said the officer.
The gang's modus operandi involved posing as passengers and alighting where their accomplices lay in wait.
"They would then pounce on the unsuspecting driver, take control of the vehicle and head to secluded places before stealing from shaken victims," the detective said.
Their bodies were taken to the Naivasha Sub County Hospital mortuary.