Kenya's incumbent President and presidential candidate of the Jubilee Party Uhuru Kenyatta (2nd R) prepares to cast his vote in Kenya's repeat presidential polls at a polling station in Nairobi, Kenya, Oct. 26, 2017.(Xinhua/Chen Cheng)

NAIROBI, Oct. 26 (Xinhua) -- Kenya's electoral body on Thursday said voting in four western counties marred by violent protests would be postponed to Saturday.

Independent Electoral and Boundaries Commission (IEBC) Wafula Chebukati said voting had been suspended in Homa Bay, Siaya, Migori and Kisumu counties, which are opposition strongholds, due to disruptions occasioned by riots and threats aimed at election officials.

Violent demonstrations have erupted in the opposition strongholds in western Kenya and Nairobi's Kibera slums as repeat presidential polls kicked off on Thursday.

The anti-election protesters engaged the police in running battles and gunshots featured across the opposition strongholds as police intensified patrols during the repeat exercise.

In Nairobi, Kibera residents burned tyres and blocked roads in a show of support for opposition leader Raila Odinga, who was President Uhuru Kenyatta's main rival.

Odinga and his running mate Kalonzo Musyoka have pulled out of the fresh polls, saying IEBC was incapable of ensuring a free, fair and credible process.

Meanwhile, Kenyan police have dismissed media reports that police officers deployed to provide security for the repeat polls have used live fire.

Police spokesman George Kinoti said only one person was killed and another sustained serious injuries in western Kenyan county of Homa Bay.

Kinoti said there were some isolated pockets of violence by gangs of youths in some parts of the five out of the 47 counties countrywide, where voting is proceeding on well.

However, independent sources confirmed three people were killed in Western Kenya -- two in the lakeside city of Kisumu and one person was killed in Homa Bay.