Africa editor, BBC World Service

Kenya police chief Joseph Boinett has been served with a court petition by lawyers representing people who say their relatives were killed by the police.

Relatives of 22 people who died in 2016 and 2017 filed a case in court last week against the head of the police and the attorney general, whom they accuse of failing to investigate the alleged killings.

Neither of them have commented on the case.

Human rights groups say there has been an increase in the number of people killed by the Kenyan police - most victims are suspected criminals in the capital, Nairobi, and Mombasa.

Local media reports that close to 200 people have been killed by the police this year.