LAGOS, (Reuters) - The final stage of Nigeria's election began on Saturday with voting for powerful state governors, two weeks after a presidential vote paved the way for the country's first democratic transfer of the top job.
The 36 governors are among the most influential politicians in Nigeria, Africa's biggest oil producer and economy, with budgets larger than those of small nations.
With so much at stake, candidates in past governorship elections have often played dirty. Ballot box snatching and shootings have marred the process in several states and at least nine people have been killed. Many results are expected to emerge on Sunday.
Muhammadu Buhari of the All Progressives Congress (APC) beat President Goodluck Jonathan of the People's Democratic Party (PDP) last month with 15.4 million votes to 13.3 million.
The vote, which Buhari won on pledges to clean up Nigeria's notoriously corrupt politics and crack down harder on the Islamist Boko Haram insurgency, was deemed free and less violent than past polls.
Yet for many Nigerians, who their governor is matters more than who sits in the capital Abuja. In the early going of Saturday's vote, however, turnout was lower than for the presidential poll in most states while in the south and southeast, voters were more apathetic after the PDP defeat on March 28 and fears of violence.
"There has been an improvement ... within some polling stations here (in Lagos), much better. In the rest of the country it depends…turnout is lower,” chief observer of the European mission Santiago Fisas told journalists in Lagos.
Sporadic violence in coastal Rivers state, Nigeria's oil hub, disrupted balloting in many districts. Voting began hours late after a 2,000-strong early morning protest in the state capital Port Harcourt delayed the distribution of materials, a Reuters witness said. Shootings on the streets of several Rivers towns forced voters to initially remain indoors, eyewitnesses and an observer said.
Five people were killed in the northwestern state of Kebbi. Four voters were shot in a scuffle with soldiers, police spokesman Nafiu Abubakar and witnesses said. Early on Saturday, an opposition party agent was killed in his residence, police and hospital sources said.
A policeman in Port Harcourt was hacked to death on Friday night and another man was killed in the area of Omoku in north Rivers on Saturday. Gunmen killed nine people in the same area a week ago.
In middle belt city, Jos, a witness Abubakar Baba said a man involved in trying to disrupt the vote was beaten by soldiers and then shot dead while trying to run away. A man was killed in southeastern Cross River state while trying to steal election materials, a police spokesman said.
Legislative elections also held on March 28 shifted power away from the PDP, which has run Nigeria since the end of military rule in 1999, to the APC, and left Buhari's party with a majority in both houses of parliament.
The APC sought on Saturday to build on its gains, while the PDP hoped to claw back some power, especially in two battlegrounds -- the megacity of Lagos, Nigeria's economic engine generating up to a third of its GDP, and Rivers.
Outgoing Lagos APC governor Babatunde Fashola is credited with transforming the metropolis of 21 million people and an economy twice the size of Kenya's with infrastructure projects, although he has also been criticised for slum clearance.
The new governors will take office in 29 states on May 29, as will Buhari.
Biometric ballot cards distributed to 56.7 million people were used for the first time in last month's vote, and helped prevent fraudulent practices like multiple voting or ballot box stuffing. They were again being used on Saturday.
"The card reader is the only way that rigging on a large scale can be stopped in this country," Abubakar Momoh, of the Independent National Electoral Commission (INEC), told Reuters.
Additional reporting by Alexis Akwagyiram and Oludare Mayowa in Lagos, Tife Owolabi in Port Harcourt, Lanre Ola in Maiduguri, Anamesere Igboeroteonwu in Onitsha and Garba Muhammed in Kebbi, Writing by Julia Payne; Editing by Mark Heinrich and Rosalind Russell