Amnesty calls for commission to probe Kenya protest deaths

"We want all police officers who killed people to be arrested," she said.

Rights groups say more than 60 people were killed during weeks of protests, initially sparked by a finance bill proposing increased taxes, with more disappearing in the weeks following the rallies.

The peaceful youth-led rallies against the controversial proposed tax hikes ballooned into wider action against President William Ruto and what many see as profligate government spending and corruption.

Amnesty's petition marks three months since the most dramatic day when protesters stormed the parliament building in Nairobi on June 25.

Based on footage and interviews with eyewitnesses, lawyers and medical professionals, Amnesty said police unlawfully used lethal weapons against peaceful protesters, killing at least six people that day.

"The right to protest in Kenya is protected under the constitution. It is unacceptable that, rather than facilitating and protecting protesters, police resorted to using deadly force," said Irungu Houghton, head of Amnesty International Kenya.

Police fired tear gas grenades "directly at protesters, sometimes at head-level," said Amnesty, adding that tear gas had been fired into at least two medical tents.

"Isolated acts of violence do not justify the use of tear gas, since it has a wide area effect. Under no circumstances should it be fired directly at individuals," said Faith Odhiambo, president of the Law Society of Kenya, in the Amnesty report.

Amnesty said it identified specific rifles, submachine guns and shotguns used by police, adding that many of them were not in uniform and in unmarked vehicles.