Police say the six men who were gunned down in Nakuru were part of a gang that has been terrorising motorists on the Nairobi highway.
The six were killed in a shootout in Section 58 on Monday evening.
Nakuru East Directorate of Criminal Investigations boss Benson Mutie told the Nation that the six carried out robberies and carjackings by impersonating police officers.
Mr Mutie said the station wagon the six were using has featured prominently in statements made by victims of the highwaymen.
He added that at least three cases of stolen goods in transit and numerous incidents of carjacking have been reported to police.
“Investigations are on as we attempt to establish the identities of the six. We may have destroyed the gang that has been a pain to motorists on the busy highway for months,” Mr Mutie said.
During the Monday operation, which was led by Nakuru county DCI chief Anthony Sunguti and Nakuru East police boss Ellena Kabukuru, the officers trailed the car that had eight occupants. It was said to be from Nairobi.
Mr Sunguti said the gang opened fire when ordered to surrender.
“Six died on the spot while two escaped with gunshot wounds,” he said.
Police said they found an assortment of weapons, including a homemade gun, police pocket phone, handcuffs and several bullets.
Mr Mutie sounded a warning to criminals operating on the highway.
“Let them know that their days are numbered. They should stop or surrender before they meet the same fate,” he said.