DAKAR (Reuters) – Niger’s ruling party candidate Mohamed Bazoum strengthened a lead over his challenger on Monday as vote-counting continued in the West African nation’s presidential run-off, electoral commission data from three-quarters of constituencies showed.

With 196 out of a total 266 constituencies counted, provisional results showed former interior minister Bazoum ahead of his challenger, former president Mahamane Ousmane, with nearly 52.9% of the vote.

The run-off vote, meant to usher in Niger’s first transition of power from one democratically elected leader to another, was held on Sunday after neither candidate secured a majority in the first round in December.

Voting was marred by the death of seven election workers after their vehicle hit a landmine on Sunday, underscoring a fraught security climate as a result of Islamist insurgencies.

One of the world’s poorest nations, Niger has also struggled with drought, floods, coronavirus and weak prices for its main export, uranium.

(Reporting by Bate Felix and Alessandra Prentice; Editing by Catherine Evans, Giles Elgood and David Gregorio)