ABUJA, Nigeria (AP) — Former military dictator Muhammadu Buhari said Wednesday it was time "to heal wounds," a day after Nigeria's president conceded defeat in a bitterly fought election.

Calling for conciliation across the political divide, Buhari said Nigerians have put a one-party state behind them and embraced democracy.

"We have voted for a president and a government that will serve and govern but never rule over you," he said. "Change has come. A new day and a new Nigeria are open to us . The victory is yours."

Buhari, 72, said Nigerians showed they can bring about peaceful change through the ballot box. When Buhari is sworn in on May 29 it will be the first time in Nigeria's history that an opposition party has democratically taken control of the country from the ruling party — considered a sign of the West African nation's maturing young democracy. President Goodluck Jonathan's party has governed since decades of military dictatorship ended in 1999.

Jonathan conceded with grace late Tuesday, saying "I promised the country free and fair elections. I have kept my word." He urged aggrieved colleagues in his People's Democratic Party to turn to the courts. "Today, the PDP should be celebrating rather than mourning. We have established a legacy of democratic freedom, transparency, economic growth and free and fair elections."

Buhari was the sole candidate of a coalition of the major political parties that formed two years ago and transformed Nigeria's political landscape by offering the first real challenge to the governing party that has been in power since 1999 in Africa's richest and most populous

Results from Saturday's election show Buhari winning votes across religious, tribal lines and geopolitical lines.

Because of decades of military rule — Buhari himself was made military ruler of Nigeria after a Dec. 31, 1983 coup — this is only the eighth election in Nigeria's history and the fifth since democracy was restored in 1999.

"You voted for change and now change has come," said Buhari, who describes himself as a convert to democracy. "Your vote affirms that you believe Nigeria's future can be better than what it is today." He was addressing supporters at his party secretariat in Abuja, the capital, around 6 a.m.

Buhari's victory was fueled by popular anger over an Islamic insurgency that has claimed thousands of lives.

Outside Buhari's party headquarters in Abuja overnight, women chanted songs and used grass brooms to elaborately sweep the way ahead of arriving dignitaries in flamboyant robes. The traditional broom is the sign of Buhari's campaign pledge to sweep out the corruption endemic in Nigeria.

"This election is not about Buhari or Jonathan, it's about Nigeria, it's about freedom, it's about change, it's about unity," Aisha Birma said, adding that Jonathan lost because he failed to provide security for Nigerians.

"What we have gone through, the Boko Haram insurgency for the past six years in Borno. ... You, Jonathan, were responsible for our lives and property. When you don't protect our lives and property, you can't talk about infrastructure, education ... Security is paramount," she said.

Jonathan's concession has defused tensions and fears of post-election violence. Some 1,000 people died and 65,000 were made homeless in riots in the Muslim north after Buhari lost to Jonathan in 2011.