Matungu MP Justus Murunga on Saturday presented himself to police in Kakamega for questioning on activities of criminal gangs in the area which have left scores of people dead in the past one month.
Western Regional Commissioner Rashid Yakub said Mr Murunga arrived at the police headquarters around 7.30am.
“The MP is being grilled by a team of detectives over the recent killings by criminal gangs in his constituency.
"He will stay in custody until Monday when he and other suspects will be presented in court,” Mr Yakub said on phone.
On Friday, police arrested former Sports CS Rashid Echesa, Kakamega Senator Cleophas Malala and Mayoni Ward Rep Libinus Oduor and gave Mr Murunga six hours to present himself to the authorities.
Mr Yakub said the four politicians will remain in custody until Monday when they will be taken to court.
He said police are pursuing more suspects who were involved in the killings by funding or inciting the young men who caused havoc.