NAIROBI, Kenya (AP) — Kenyan police have fired tear gas and warning shots to disperse small groups of opposition protesters ahead of a presidential election on Thursday that opposition leader Raila Odinga plans to boycott.

The sporadic confrontations in downtown Nairobi on Tuesday occurred amid bustling traffic and forced some city workers and passers-by to race away from the acrid clouds of tear gas.

A police officer told The Associated Press that he and his colleagues were firing blanks.

Human rights activists have said police fatally shot 67 people since the Aug. 8 election whose annulment by the Supreme Court opened the way to the new vote.

President Uhuru Kenyatta, who was declared the winner in the August vote, wants to press ahead with the new election despite concerns about its credibility.