The attackers moved from house to house with a list of suspected witches
Kenya police have arrested 86 people in connection with killing of 11 elderly people suspected of being witches.
Last week, eight women and three men were burned to death in the western Kisii district, where belief in witchcraft is widespread.
A police spokesman told the BBC that those arrested may face charges ranging from murder to robbery with violence.
Investigations were still under way, he said, but those charged with murder could face the death sentence.
Five of the suspects were found in possession of property and livestock belonging to some of the victims and will be tried for violent robbery, deputy police spokesman Charles Owino said.
"Somebody has a responsibility to teach them a lesson," he told the BBC.
He said that the suspects could appear in court by June 10, after investigations were completed.
The BBC's Muliro Telewa in the region says although those suspected of engaging in witchcraft have been killed or ostracised in the past, it was a surprisingly large number of people to be attacked at the same time.
The mob dragged the victims out of their houses and burned them individually and then set their homes alight.
Villagers told reporters that they had evidence that the victims were witches.
They say they found an exercise book at a local primary school that contained the minutes of a "witches' meeting" which detailed who was going to be bewitched next.