Kenyans are casting ballots in their country's presidential election, bringing to a close yet another turbulent campaign season in the economically vital East African nation.

Voters began lining up hours before dawn Tuesday to cast their ballots in hotly contested nationwide polls. One voter, 31-year-old Mildred Malubi, said she waited in line for three and a half hours to vote in Kangemi slum, in Nairobi.

This year's election is the second consecutive election between the incumbent, 55-year-old Uhuru Kenyatta, and his longtime rival, 72-year-old Raila Odinga, who is making his fourth run for the presidency. Kenyatta has the support of Kenya's majority Kikuyu ethnic tribe, while Odinga is favored by ethnic Luo people.

The campaign has been marred by accusations of vote rigging made by Odinga against the president, and the murder of a top-ranking election official. The heightened tensions have raised concerns of a repeat of the disputed 2007 vote, when more than 1,100 were killed and 600,000 more displaced in a wave of ethnic violence.

Former U.S. President Barack Obama, whose father was born in Kenya, issued a statement Monday calling on all Kenyans to "reject violence and incitement."

"I urge all Kenyans to work for an election — and aftermath — that is peaceful and credible, reinforcing confidence in your new Constitution and the future of your country," Obama wrote.

Thousands of election observers have been deployed throughout Kenya, including former U.S. Secretary of State John Kerry.

The polls close at 5 pm local time. Results are expected by Friday.

肯尼亚选民开始总统大选投票，让这个东非重要国家又一场紧张骚动的选战进入尾声。

选民们星期二天亮前好几个小时就开始在投票站外排队等候，在这次竞争异常激烈的选战中投下自己的一票。一个31岁的选民说，他在内罗毕坎吉米贫民窟的投票站外排了三个半小时的队。

这是55岁现任总统肯雅塔和他的长期政敌，72岁的奥廷加之间连续第二次较量，也是奥廷加第四次参选总统?？涎潘玫搅丝夏嵫钦既丝诙嗍幕庥茸迦说闹С?，而奥廷加则深受卢奥族人的爱戴。

奥廷加指责肯雅塔总统在选举中有舞弊行为，外加一名负责选举事务的高级官员被谋杀，都给这次大选带来了瑕疵。紧张局势的加剧让外界担心，2007年选举纠纷引起的民族暴力会重演，那一轮暴力共造成1100多人被杀，60多万人流离失所。

美国前总统奥巴马的父亲出生在肯尼亚。奥巴马星期一发表声明，呼吁所有肯尼亚人“拒绝暴力和煽动”。

奥巴马写道：“我敦促所有肯尼亚人，为和平可信的选举和选举后续工作努力，巩固对你们的新宪法和你们国家未来的信心?！?/p>

数千名选举观察员前往肯尼亚各地监督选举，其中也包括美国前国务卿克里。

投票站定于当地时间下午五点关门。选举结果预计星期五公布。

Kenyans are casting ballots in their country's presidential election, bringing to a close yet another turbulent campaign season in the economically vital East African nation.

Voters began lining up hours before dawn Tuesday to cast their ballots in hotly contested nationwide polls. One voter, 31-year-old Mildred Malubi, said she waited in line for three and a half hours to vote in Kangemi slum, in Nairobi.

This year's election is the second consecutive election between the incumbent, 55-year-old Uhuru Kenyatta, and his longtime rival, 72-year-old Raila Odinga, who is making his fourth run for the presidency. Kenyatta has the support of Kenya's majority Kikuyu ethnic tribe, while Odinga is favored by ethnic Luo people.

The campaign has been marred by accusations of vote rigging made by Odinga against the president, and the murder of a top-ranking election official. The heightened tensions have raised concerns of a repeat of the disputed 2007 vote, when more than 1,100 were killed and 600,000 more displaced in a wave of ethnic violence.

Former U.S. President Barack Obama, whose father was born in Kenya, issued a statement Monday calling on all Kenyans to "reject violence and incitement."

"I urge all Kenyans to work for an election — and aftermath — that is peaceful and credible, reinforcing confidence in your new Constitution and the future of your country," Obama wrote.

Thousands of election observers have been deployed throughout Kenya, including former U.S. Secretary of State John Kerry.

The polls close at 5 pm local time. Results are expected by Friday.

肯尼亚选民开始总统大选投票，让这个东非重要国家又一场紧张骚动的选战进入尾声。

选民们星期二天亮前好几个小时就开始在投票站外排队等候，在这次竞争异常激烈的选战中投下自己的一票。一个31岁的选民说，他在内罗毕坎吉米贫民窟的投票站外排了三个半小时的队。

这是55岁现任总统肯雅塔和他的长期政敌，72岁的奥廷加之间连续第二次较量，也是奥廷加第四次参选总统。肯雅塔得到了肯尼亚占人口多数的基库尤族人的支持，而奥廷加则深受卢奥族人的爱戴。

奥廷加指责肯雅塔总统在选举中有舞弊行为，外加一名负责选举事务的高级官员被谋杀，都给这次大选带来了瑕疵。紧张局势的加剧让外界担心，2007年选举纠纷引起的民族暴力会重演，那一轮暴力共造成1100多人被杀，60多万人流离失所。

美国前总统奥巴马的父亲出生在肯尼亚。奥巴马星期一发表声明，呼吁所有肯尼亚人“拒绝暴力和煽动”。

奥巴马写道：“我敦促所有肯尼亚人，为和平可信的选举和选举后续工作努力，巩固对你们的新宪法和你们国家未来的信心?！?/p>

数千名选举观察员前往肯尼亚各地监督选举，其中也包括美国前国务卿克里。

投票站定于当地时间下午五点关门。选举结果预计星期五公布。