Former Senegalese prime minister has conceded the presidential election to the opposition candidate based on preliminary results a day after the vote, according to a statement by his campaign.

Amadou Ba said on Monday he congratulated Bassirou Diomaye Diakhar Faye and wished him success.

Faye’s expected victory reflected frustration among youth with high unemployment and concerns about governance in the West African nation. Faye, backed by popular opposition leader Ousmane Sonko, has vowed to protect Senegal from corruption and interference from foreign powers like former colonial master France.

There was no immediate comment from Faye’s team. Sonko was barred from the presidential race in January for a prior conviction, and Faye ran in his place.

The election on Sunday followed months of uncertainty and unrest after President Macky Sall’s unsuccessful attempt to postpone it until the end of the year. The sometimes deadly protests that followed shook Senegal’s reputation as a stable democracy in a region that has seen a wave of coups in recent years. Rights groups said dozens were killed while hundreds more were jailed.

The vote was largely peaceful with a high turnout, observers said. Official announcements are expected later this week, but early counts showed voters turned out overwhelmingly in favour of the opposition.

In Senegal’s coastal capital, Faye’s supporters danced and played music until late Sunday night in anticipation of victory.

“Our democracy will emerge stronger from these results,” said Ndeye Sow, 27. “We’re delighted, there was no violence here serenity is the order of the day.”

More than seven million people were registered to vote in a country of roughly 17 million. This is Senegal’s fourth democratic transfer of power since gaining independence from France more than six decades ago. The outgoing president was constitutionally barred from seeking a third term.

• An AP report