DCI detectives arrested seven people on Wednesday night believed to members of the Kabonokia Sect at Gatue, Tharaka Nithi County.
Police said the seven refused to give information to enumerators in the ongoing census process.
The suspects claimed that the census process is satanic and they alleged to be counted in heaven.
Meru town chief Mercy Murithi told the Star on Tuesday that security had been tightened.
She said that two enumerators are escorted by one police officer and area manager.
She said that Kabonokia sect had threatened enumerators during the pre-listing and agreed to be counted after getting a warning from the authorities.