Frontrunner flies back to Nigeria

Wild rumours circulated in Nigeria after Mr Yar'Adua's collapse

Nigeria's ruling party presidential contender, Umaru Yar'Adua, has arrived back in Nigeria and is to resume campaigning for April's election.

He landed in Lagos, after flying to Germany last week for medical tests when he collapsed at a campaign rally.

The 55-year-old is the frontrunner to win the election and has previously suffered from a kidney illness.

His collapse prompted speculation that he could be replaced as the People Democratic Party's candidate.

Mr Yar'Adua told the BBC earlier this week that he had suffered from breathlessness and had taken his doctor's advice to have a thorough medical check-up abroad.

Mr Yar'Adua was a relatively unknown northern Muslim governor before he won the governing party primaries with the backing of President Olusegun Obasanjo - who steps down after two terms in power.

As the governing party's candidate, he is widely considered to be the favourite to become Nigeria's next president.

He faces two other strong contenders: Vice-President Atiku Abubakar who is standing for the opposition Action Congress and former military leader Gen Muhammadu Buhari.

The polls should become the first transfer of power in Africa's most populous country from one elected leader to another since independence in 1960.