A politician from Brazilian President Luiz Inacio Lula da Silva’s party was injured when attackers threw stones and bottles at a campaign vehicle on the eve of Sunday’s crucial presidential runoff.

The violent incident came as Brazilians voted in a tightly contested election between left-wing incumbent Lula, who has championed closer ties with BRICS nations, and right-wing challenger and Donald Trump ally Flavio Bolsonaro.

Montes Claros City councilwoman Iara Pimentel, a member of Lula’s Workers’ Party (PT), was struck in the face during a campaign event late Saturday night in Minas Gerais state in southeastern Brazil, according to state news agency Agencia Brasil (ABr).

Video footage showed bottles, bricks, and other objects being thrown at the campaign vehicle carrying the politician. Later images showed her bloodied face.

She was taken to a local hospital by ambulance, ABr reported.

“Thinking differently is a right. Political violence is a threat to democracy. No disagreement can justify acts of aggression or put lives at risk,” Pimentel said in a statement cited by the agency.

Ana Elisa, a 21-year-old congresswoman-elect from Lula’s Workers’ Party representing Minas Gerais, condemned the attack and called for those responsible to be held accountable.

Lula also condemned what he described as multiple incidents of violence during the election.

“The most sacred thing in democracy is democratic coexistence in diversity,” he said, according to ABr, arguing that neighbors should be able to support different political candidates and sports teams or hold different beliefs without resorting to violence.

The assault occurred just hours before polls opened on Sunday and weeks after the close of the first round of Brazil’s presidential election on October 4. Lula received just over 45%, while 47% went to Flavio Bolsonaro, the son of former Brazilian President Jair Bolsonaro – who is serving a 27-year prison sentence for plotting a coup following his 2022 election defeat. Trump has described the former president’s prosecution as a “witch hunt.”

The election has also been marred by allegations of interference by US tech giant Meta, the parent company of Facebook, Instagram, and WhatsApp. Meta blocked the Facebook advertising account used by Lula’s team ahead of the first round on October 4, then prevented his official Instagram account from boosting posts days later, according to campaign officials.

Meta denied politically interfering in the election, but internal company messages acknowledged technical restrictions affecting Lula’s Instagram account, Folha de S.Paulo newspaper reported last week, citing internal communications.