Supporters of the losing candidate in Niger’s presidential election burnt tires, threw rocks and set several buildings on fire on Thursday, in a third day of violent demonstrations in the capital Niamey.

Niger’s electoral commission on Tuesday declared ruling party candidate Mohamed Bazoum the winner of Sunday’s runoff election with 55.75% of the vote, but his rival, Mahamane Ousmane, a former president, has alleged fraud and claimed he won with 50.3%.

The election is meant to lead to the first transition from one democratically elected leader to another following 4 coups since independence from France in 1960. President Mahamadou Issoufou is stepping down after 2 five-year terms.

Late on Wednesday, the national prosecutor said many people had been arrested in the protests. Internet access has also been severely restricted since Wednesday.

Small groups of Ousmane supporters again took to the streets on Thursday to lob rocks at police and national guard troops, who responded by firing tear gas.

Some demonstrators burnt private houses, including that of Radio France Internationale (RFI) correspondent Moussa Kaka, according to a Reuters witness .

Kaka and his family are safe, RFI said in a statement, denouncing what it called “a grave attack on freedom of the press”.

Ousmane, who served as president from 1993 until 1996, when he was overthrown by the military, said on Wednesday that he reserved the right to appeal the election result in the courts.

The vote was held “under free, fair, credible and transparent conditions,” said an observer mission from the Economic Community of West African States.

Nonetheless, it was marred by 2 attacks that claimed the lives of 8 election workers in parts of Niger where Islamist militants regularly target civilians and the military.