Malian President Ibrahim Boubacar Keita has been elected for a second five-year term after winning a runoff ballot by a landslide, according to official figures released Thursday.
The election was closely watched abroad as Mali is a linchpin state in the jihadist insurgency raging in the Sahel.
Keita, 73, picked up 67.17 percent of Sunday's vote against 32.83 percent for opposition challenger and former finance minister Soumaila Cisse, 68, who also ran against Keita in 2013. Turnout was low at 34.5 percent.
"I thank you from the bottom of my heart for putting your trust in me once more," Keita said on his Facebook page.
But Cisse's party angrily vowed to contest the results, using "all democratic means."
Mali, a landlocked nation home to at least 20 ethnic groups where most people live on less than $2 (1.76 euros) a day, has been battling a years-long Islamic revolt which has stoked intercommunal violence.
Hundreds of people have died this year alone, most of them in Mopti, an ethnic mosaic in central Mali, in violence involving the Fulani nomadic herder community and Bambara and Dogon farmers.
Keita's response to the burgeoning crisis was the big campaign issue, with opposition candidates rounding on him for alleged incompetence or indifference.
But the verbal assaults failed to dent his core support, and a fractured opposition and widespread voter apathy left him firm favourite in the final round.
"We are very happy, Mali has won," Sirandou Soumare, a Keita supporter, told AFP in Bamako. "We want everyone to come together for peace in Mali."
Voting was marred by jihadist attacks that forced the closure of a small percentage of polling stations, and by allegations of ballot-box stuffing and other irregularities.
- 'Fraud' claim -
Cisse had already said he would reject the results.
He called on "all Malians to rise up... We will not accept the dictatorship of fraud" -- a verbal broadside that triggered a UN appeal for calm.
UN Secretary-General Antonio Guterres had spoken by phone with the two leaders to stress "the need to always keep the Malian people first, and not to go backwards on the reconciliation effort at a crucial moment," UN spokesman Farhan Haq said.
On Thursday, as Keita supporters rejoiced, some of Cisse's supporters rallied in Bamako, refusing to accept that their candidate will not be president.
Around 100 scooters and a few dozen cars took part in the demonstration.
"We are like gold panners who have just been robbed of the gold nugget they have just found," one supporter said.
Campaign chief Tiebile Drame meanwhile lashed the results as bogus.
"These are their results. They do not reflect the truth of the polls," Drame said.
Cisse plans to appeal to the Constitutional Court "to get the fraudulent results cancelled" in some regions, Drame said.
"They just stole our voice, we cannot accept that," added another supporter, Abdramane Sow, a 26-year-old computer technician as he prepared to demonstrate.
Observer missions sent by the European Union and the African Union (AU) have issued provisional reports saying the election was not badly impaired.
"Our observers did not see fraud but irregularities," EU mission chief Cecile Kyenge said. The AU said voting was conducted "in acceptable conditions."
- Challenges -
Keita faces high expectations to boost a 2015 peace accord between the government, government-allied groups and former Tuareg rebels.
The credibility of the deal -- billed by Keita as the cornerstone of peace -- has been battered by a state of emergency that heads into its fourth year in November.
France, which intervened to root out jihadists in northern Mali in 2013, still has 4,500 troops in the country.
They are deployed alongside the UN's 15,000 peacekeepers and a regional G5 Sahel force, aimed at fighting the insurgents and restoring the authority of the state in the lawless north.
French President Emmanuel Macron congratulated Keita on his election victory and reiterated France's commitment to the country's security and economic development, his office said Thursday.
Income per capita has fallen since 2014, according to the World Bank, and nearly half of the 18 million population live in poverty.