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By Helen Nyambura-Mwaura and Wangui Kanina
NAIROBI, Dec 29 (Reuters) - Kenya’s presidential rivals were neck-and-neck on Saturday with nearly 90 percent of official results counted and accusations of rigging that ignited ethnic violence across the east African nation.
Several people died in the unrest.
As night fell with the election on a knife-edge and further results not due until morning, Kenyans kept off the streets, police manned roadblocks and politicians huddled to strategise.
The latest results showed President Mwai Kibaki grabbing a lead, infuriating supporters of opposition challenger Raila Odinga, who led in early tallies and in most opinion polls in the run-up to Thursday’s election.
Odinga’s political allies, accusing the government of a plot to rig the result, tried to shout down the head of the Electoral Commission of Kenya (ECK) as he read out the figures that gave Kibaki a lead of roughly 120,000 votes.
Amid the confusion, the exasperated chairman then gave only an earlier official tally giving Odinga a 38,000 vote lead.
The commission then announced abruptly that it would stop reporting results for the night, leaving most of Kenya’s 36 million people in suspense.
"We are Kenyans, not beasts!" ECK chairman Samuel Kivuitu told scores of party agents, politicians and journalists crammed into the Nairobi conference centre ringed by armed guards.
The delays announcing the official results fuelled tensions across the nation, with political parties trading accusations of rigging and riots erupting in most major cities.
Both Odinga’s Orange Democratic Movement (ODM) and Kibaki’s Party of National Unity (PNU) claimed victory and the leadership of the region’s biggest economy for the next five years.
Throughout the day, youths from rival tribes fought, looted and burned homes, mostly in opposition strongholds.
Police fired teargas and up to six people died, according to witnesses and local media. The scenes marred what foreign observers had praised as broadly peaceful polls on Thursday.
Britain’s foreign minister, David Miliband, called for an end to violence and said it was vital for all Kenyan political leaders to act responsibly and respect democracy.
If Odinga — a wealthy businessman who paints himself as a champion of the poor — fulfils a long-held ambition to lead Kenya, Kibaki would become the first of the country’s three post-independence leaders to be ejected by the ballot box.
From Kisumu in the west to Mombasa on the coast and many towns in between, trouble broke out on Saturday pitting Odinga’s Luo supporters against members of Kibaki’s Kikuyu ethnic group.
The tribes, two of Kenya’s biggest, have a long history of rivalry during the country’s four decades of independence.
"We are sensing a plan to rig the elections," taxi cyclist Eric Ochieng, 18, told Reuters in the middle of riots in Kisumu city, in Odinga’s homeland. "We will not accept this."
Residents said one person was killed in Kisumu — a normally sleepy city by Lake Victoria — as hundreds of youths took to the streets, burning tyres, ransacking shops and blocking roads.
"The government has failed to declare Odinga the winner," said 11-year-old Kennedy Ochieng, stumbling under the weight of a box of clothes, mobile phone chargers and other stolen goods.
"They stole our votes so we are looting everything we can."
As black smoke billowed overhead, one crowd waved machetes and yelled "Death to Kikuyus". Young boys swigged looted beer.
"We have just started. We will loot all Kikuyu shops and kill them on sight," said Richard Ondigi, 23, a driver.
Locals said two people were killed in another hotbed of support for Odinga, Nairobi’s huge Kibera shantytown, where shots were fired and dozens of shacks burned to the ground.
Groups of youths protested elsewhere in Nairobi and city centre streets were near deserted as business owners pulled down their shutters. Truckloads of armed police patrolled.
Police boss Hussein Ali told a news conference his officers would "continue to take action against hooligans without fear or favour", and foreign observers appealed for calm.
"People must exercise statesmanship. This is not about Luos and Kikuyus, but all of Kenya," U.S. ambassador Michael Ranneberger told reporters while flanked by Western envoys.
If Odinga does seal victory, he will realise a dream that eluded his late father Jaramogi Oginga Odinga, a nationalist hero who became vice-president. Kibaki says he will double economic growth for Kenyans if he is re-elected.
The inauguration of Kenya’s next president was due in days.
If it is Odinga, his priority will be to enlist support of the economically powerful Kikuyus, ensure a peaceful handover and allay business fears that he is a left-wing radical.
Kibaki would have a tough time appeasing the opposition if he returns to State House. (Additional reporting by Guled Mohamed in Kisumu; Noor Khamis, Tim Cocks, Bryson Hull, George Obulutsa, Joseph Sudah, Duncan Miriri, Katie Nguyen and Nicolo Gnecchi in Nairobi; Writing by Daniel Wallis; Editing by Andrew Cawthorne and Matthew Tostevin)