What is happening in Kenya today?

Kenya is holding a presidential election rerun because the Supreme Court nullified the results of the August 8 poll, which was won by President Uhuru Kenyatta. The court said there were "irregularities and illegalities" in the voting process.

Opposition leader Raila Odinga, who masterminded the annulment, is boycotting Thursday's rerun race because he says the electoral reforms he demanded never happened. His supporters have joined his protest and are not turning out to vote.

How is it going so far?

Not too well. At least three people have been killed; there are reports of clashes in opposition strongholds, with protesters barricading roads and burning tyres and police firing tears gas and live ammunition. You can keep up to date with all of the latest developments here.

Why is there so much tension?

The opposition candidate, Raila Odinga, has repeatedly charged that the first election was not free and fair. He thinks today's vote is also full of challenges, because the electoral body did not make the reforms he demanded. Because of this, he is boycotting the vote.

What reforms did Odinga request?

The August poll marked the first time Kenya used a new electronic voting system because, during previous elections, the electoral commission was often accusations of stealing votes. However, despite new system in place, the opposition contested this year's results. Odinga claimed hackers infiltrated the database of the election body to manipulate the "democratic process".

Odinga wanted reforms to make the vote credible, and demanded, for instance, top officials from the electoral commission to be removed.

So without Odinga, who's in the running?

President Uhuru Kenyatta, who won 54 percent of the previous vote in August, and six of minor candidates - none of whom scored more than one percent in the previous poll.

Is today's vote considered free and fair?

That depends on who you talk to. Javas Bigambo, a political analyst in Nairobi, the Kenyan capital, told Al Jazeera that he has doubts.

Today's violence "contributes to the conclusion that this election may not be very credible in the end", he said. "It is a failed rerun because so far, from a spot-check across the country, it is evident that the boycott is successful ... If close to half the country will not participate in this election, then the very question of legitimacy of this election upon its conclusion may arise."

What does Kenyatta make of it all?

In a response to the annulment, incumbent President Kenyatta said he "personally disagreed" with the ruling but he would "respect it, as much as I disagree with it".

On the eve of Thursday's rerun, he called on Kenyans to turn out. In a televised address, Kenyatta said "the rights of those who wished not to vote" were protected by the country's constitution.

Will there be a third vote?

It's too early to say what will happen next. If Kenya's recent political movements have shown anything, it's that they are hard to predict.

Bigambo, the analyst, said that more unrest could see Kenyatta feel compelled to find a way of "bridging that divide and extending an olive branch to the opposition leadership to take this country forward".

More unrest? Why what's happened so far?

Amnesty and Human Rights Watch said that at least 67 protesters have been killed in demonstrations so far, since the August election. Odinga, angered by the fact electoral reforms had not taken place, had called for daily rallies. The government then banned protests in three major cities.

With so much political wrangling, is there voter fatigue?

Our reporter found traces of this earlier in the week, in Nairobi. A lot of business owners were also disappointed, saying the political impasse has lost them income. However, although many opposition supporters seem to have boycotted the vote, others queued before sunrise to vote. Turnout figures will come out later.