"It is worrying that during the demonstrations witnessed since July, we have documented 27 persons shot dead by police...this must not continue and must be brought to an end immediately," said Bishop Okinda.
They called on the opposition and government to embrace dialogue to stop ongoing protest that has seen many killings across the country.
The human rights defenders on Friday faulted the police service for killings, numerous injuries and abductions of protesters.
The groups says they have documented 27 deaths, 43 abductions of human rights activists and numerous others nursing gunshot wounds.
"We are witnessing a disturbing police operation that exposes the country to civil strife and informal repression," said Wanjiru Gikonyo, board member Kenya Human Rights Commission (KHRC).
She accused the police of working with what she termed private militia to attack, maim and execute protesters especially in Nairobi.
Ms Gikonyo alleged that last Wednesday's Mlolongo area deaths were "state-ordered executions" conducted by rogue police officers.
Police Reforms Working Group-Kenya (PRWG-Kenya) claimed the police have designed unlawful tactics to violate the rights of protesters.
"We are disturbed by cases of police officers masquerading as journalists on duty with intentions of arresting protesters," said Peter Kiama of PRWG-Kenya.
Mr Kiama said the actions contravenes the Criminal Procedures Code and Police Standing Orders and that such unethical conducts risks the life of journalists on duty.
National Integrity Alliance through Executive Director Sheila Masinde decried increased, targeted-attacks against human rights defenders during protests.
She asked the police to unconditionally release those arrested and abducted promising to take legal action against the perpetrators of the assaults.
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