Nigerian President Umaru Yar'Adua, long plagued by poor health, has died at age 58, his spokesman said.
Yar'Adua died at 9 p.m. (2000 GMT) Wednesday at the Aso Rock presidential villa, presidential spokesman Olusegun Adeniyi told The Associated Press. Adeniyi, his voice cracking, said Yar'Adua's wife Turai was at his side when he died. Adeniyi did not give a cause of death.
Yar'Adua, a Muslim, will be buried Thursday, Adeniyi said.
Yar'Adua went to a Saudi Arabian hospital on Nov. 24 to receive treatment for what officials described as a severe case of pericarditis, an inflammation of the sac surrounding the heart that can cause a fatal complication. He failed to formally transfer his powers to Vice President Goodluck Jonathan, sparking a constitutional crisis in Nigeria, Africa's most populous nation with 150 million people.
Jonathan assumed the presidency Feb. 9 after a vote by the National Assembly while Yar'Adua was still in Saudi Arabia. Lawmakers left open the possibility for Yar'Adua to regain power if he returned to the country in good health. He returned on Feb. 24 but never appeared in public and did not assume power again.
Yar'Adua took office in 2007 in a country notorious for corruption and gained the accolades of many for being the first leader to publicly declare his personal assets when taking office -- setting up a benchmark for comparison later to see if he misappropriated funds. But enthusiasm for his presidency waned as time past and little changed in a country burdened by years of entrenched corruption.
However, Yar'Adua sought to end the violence in the oil-rich Niger Delta. The Movement for the Emancipation of the Niger Delta has been attacking oil installations, kidnapping petroleum company employees and fighting government troops since January 2006 in what it called a protest against the unrelenting poverty of people in the Niger Delta.
The unrest had cut Nigeria's oil production by about a million barrels a day, allowing Angola to overtake it as Africa's top oil producer.