This man jumped out of the window after voting, due to the crowds

First results are trickling in, and a number of government ministers have lost their seats in parliament.

But the presidential race between Mwai Kibaki and his main challenger Raila Odinga is too close to call.

International observers praised the polls as generally smooth and fair. Final results from a "massive" turnout are not expected until Saturday.

A spokesman for Electoral Commission of Kenya (ECK) told the BBC that turnout had perhaps been more than 70%, from an electorate of 14m.

Correspondents say that in Kenya's previous elections, the outcome has been obvious before polling, or at least there has been a strong favourite.

When Mr Odinga first turned up to vote in the Nairobi slum of Kibera, his name was missing from the electoral register - like many other people whose names began with "R" or "O".

The BBC's Karen Allen in Kibera says this will fuel suspicions of a plot to rig the election, although other say it was merely a bureaucratic mix-up.

Mr Odinga, who has led recent opinion polls, was allowed to vote later - to cheering crowds in the constituency he represents in parliament.

Milking delayed

There is tight security around the Kenyatta International Conference Centre in Nairobi, where the results will be announced.

Among those to lose their seats are the vice-president, Moody Awori, and the ministers for local government and information.

Kibaki: Dream or nightmare? Odinga: King-maker

At an overnight news conference, the ECK head, Samuel Kivuito, said there had been delays in voting and counting, and the process of compiling results was going slowly.

Some say the huge numbers overwhelmed the authorities. The queue of voters stretched for more than a kilometre outside some polling stations.

Mr Kibaki was able to vote unhindered in the central town of Nyeri.

"I am sure we will win. Thank you Kenyans for giving me an opportunity and I will not tire serving you," he said.

People started to queue before dawn.

I can see people shaking their fists BBC's Ruth Nesoba, Kibera At the polls: Reporters' log Voters' views

"I have not even milked my cow because today we are putting our country first," said Mary Muthoni Gikiri as she waited to vote in Mr Kibaki's hometown of Othaya, some 200km (125 miles) from the capital, Nairobi.

In the North-Eastern Province, one old man collapsed and died while waiting to vote.

Tempers frayed in Kibera, where voting was delayed for about six hours.

Because so many names were missing from the voters' roll, officials said people could vote with their national identity card and voter registration card and voting was extended by two hours.

A man has been shot dead in Kibera - police say it was criminal, but Mr Odinga's Orange Democratic Movement (ODM) says it was political.

Evidence

Earlier, chief EU election monitor Alexander Graf Lambsdorff invited anyone with evidence of election fraud to come forward.

Vote in pictures

"As far as allegations of rigging are concerned, they are just that - allegations," he told the BBC.

Mr Odinga's supporters have accused the president of using state security agents to help rig the polls.

Three police officers were killed in Kisumu, after the opposition alleged that they were carrying pre-marked ballot papers.

The president has denied involvement in any election fraud.

More than 14 million Kenyans are eligible to vote - they are also voting in parliamentary and local elections.

President Kibaki, running under the banner of a broad-based coalition known as the Party of National Unity, hopes his economic record will secure a second term.

Mr Odinga played a key role in Mr Kibaki's 2002 victory. But the pair fell out soon afterwards.

Mr Kibaki's critics accuse him of failing to keep his promise to tackle corruption.

There are six other candidates standing in the presidential elections.

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