A witness says hundreds of protesters are rioting in Kisumu, a city in southwestern Kenya that is a stronghold of opposition leader Raila Odinga. Kenyan journalist Fred Ooko says people from the Kondele slum in Kisumu burned tires and blocked roads on Wednesday. Kisumu, a port city on Lake Victoria, is one of Kenyaa��s largest urban centers. Authorities have been concerned about possible violence following elections on Tuesday. Opposition leader Raila Odinga has alleged fraud following the release of results showing him trailing President Uhuru Kenyatta by a wide margin.