Cord leader Raila Odinga on Monday took swipe at the police telling them to prioritise protecting lives and property of Kenyans.
Raila said recent actions by the police against opposition supporters protesting against the Independent Electoral and Boundaries Commission (IEBC) were illegal.
"The police must cease and desist their reckless and partisan posturing that only serves to inflame passions and set the country on a course to chaos," he said on Monday at his Capitol Hill office after leading protests disrupted by heavily armed police long University Way in Nairobi.
"That said, we will not relent in demanding for the departure of the IEBC commissioners and reform of the Secretariat as the irreducible minimum for free and fair elections."
Raila has been leading opposition protests aimed at ejecting IEBC Chairman Isaack Hassan and other commissioners from office.
The opposition chief accuses the IEBC of favouring the ruling Jubilee coalition.
He has maintained Cord will not participate in the 2017 general elections unless the IEBC is reconstituted.
Raila accuses Mr Hassan and his team of being too corrupt to be entrusted to conduct any election.
Hassan on his part on May 5, told Raila to table any evidence he has to prove that he and his team are corrupt.
He told the opposition to use Parliament in their quest to disband the electoral body.
Raila on Monday led other Cord Co-Principals Kalonzo Musyoka and Moses Wetangula, Kanu Secretary General Nick Salat and opposition supporters in agitating for the disbandment of the IEBC.
The countrywide protests were however, disrupted by teargas wielding police officers.
Other counties which took part in the demos included Mombasa, Kisumu, Siaya, Meru and Kakamega.
Since the demonstrations began four weeks ago, four people have been killed with police being accused of orchestrating the deaths.
During April 23 demonstrations in Kisumu, three people were shot dead.
"We have made it clear from the onset that we are engaging a peaceful popular action protected by Article 37 of the Constitution yet the police have repeatedly and with no provocation chosen to use excessive force to disperse our legal assembly," he said.