NAIROBI, Kenya (AP) -- Five years after more than 1,000 people were killed in election-related violence, Kenyans on Monday began casting votes in a nationwide election seen as the country's most important -- and complicated -- in its 50-year history.
Police issued alerts late Sunday of impending attacks, and the violence began even before the voting. Police in the coastal city of Mombasa reported a 2 a.m. attack by a gang of dozens; early reports indicated several officers -- perhaps four or five -- were killed.
Multiple factors indicated violence was likely: The police said late Sunday that criminals were planning to dress in police uniforms and disrupt voting in some locations.
In addition, intelligence on the Somali-Kenya border indicated Somali militants planned to launch attacks; a secessionist group on the coast threatened -- and perhaps already carried out -- attacks; the tribes of the top two presidential candidates have a long history of tense relations; and 47 new governor races are being held, increasing the chances of electoral problems at the local level.
Perhaps most importantly, Uhuru Kenyatta, one of two top candidates for president, faces charges at the International Criminal Court for orchestrating the 2007-08 postelection violence. If he wins, the U.S. and Europe could scale back relations with Kenya, and Kenyatta may have to spend a significant portion of his presidency at The Hague.
Kenyatta's running mate, William Ruto, also faces charges at the ICC.
Kenyatta, a Kikuyu who is the son of Kenya's founding president, faces Raila Odinga, a Luo whose father was the country's first vice president. Polls show the two in a close race, with support for each in the mid-40-percent range. Eight candidates are running for president, making it likely Odinga and Kenyatta will be matched up in an April run-off, when tensions could be even higher.
Near the Somali border, Garissa County Commissioner Mohamed Ahmed Maalim said Sunday that officials intercepted communications that indicated terror attacks were planned, including explosive attacks and kidnappings. "They are planning to interrupt the elections, but we will not allow them do so," he said.
Maalim said soldiers are patrolling the region to prevent attacks from al-Shabab, the al-Qaida-linked Somali militant group. He said 300 specialized troops known as GSU are patrolling the Dadaab refugee camp, where more than 400,000 Somalis live.
In Mombasa, police officer Aggrey Adoli said Monday that police were attacked by a marauding gang while on patrol.
At the Nairobi Chapel, an evangelical church in the capital, three pastors took turns Sunday praising the attributes of some tribes, drawing cheers from the congregation. The Kikuyus were praised for being entrepreneurial, the Luos for valuing education, and the Kalenjins -- Ruto's tribe -- for their loyalty.
"Tomorrow we celebrate our cultural diversity as a nation," Nick Korir said in his sermon.
"We ask you to shame all prophets of doom," a cleric at an evangelical church in Nairobi called Mavuno told a packed congregation. "This is a country we are all proud of despite the divisions that people talk about. There is a Kenya after tomorrow."
In the weeks leading up to Monday's vote, described by Odinga as the most consequential since independence from the British in 1963, peace activists and clerics have been praying that this time the election is peaceful despite lingering tensions.
Odinga's acrimonious loss to President Mwai Kibaki in 2007 triggered violence that ended only after the international community stepped in. Odinga was named prime minister in a coalition government led by Kibaki, with Kenyatta named deputy prime minister.
The candidates held their final rallies Saturday, a day of political attacks and denials following published comments in the Financial Times attributed to Odinga that election violence could be worse than 2007-08 if the vote is rigged.
The Financial Times on Sunday said that its story, because of an editing error, "may have left the incorrect impression" that Odinga "would not respect the result of a free and fair presidential election. We are happy to be able to clarify this point."
Some 99,000 police officers will be on duty during an election in which some 14 million people are expected to vote. Kenyans will also be electing new lawmakers, governors and other officials.
Kenyatta, 51, the son of Jomo Kenyatta, the country's founding president, is one of the country's wealthiest men. He studied at Amherst College in the U.S. before returning home to become a businessman and later his father's political heir.
In 2011 Forbes magazine listed him as the wealthiest Kenyan, worth at least $500 million, although he was dropped from a subsequent list because his personal wealth was hard to separate from that of his close relatives. The Kenyattas are said to own hundreds of thousands of acres of prime land across the country, a controversial point in a nation where millions do not own even a small plot of land.