SAO PAULO (AP) — Brazilian police said on Monday that a 39-year-old supporter of former President Luiz Inácio Lula da Silva was stabbed to death in a bar amid rising concern about political violence in a tense presidential campaign.

The newspaper O Povo reported that witnesses told police a man entered a bar in the city of Cascavel on Saturday and asked who was voting for da Silva in the Oct. 2 election. A man said, “I will,” and then was stabbed. He died in hospital the same day.

A Ceara state police official confirmed the report Monday, speaking on condition of anonymity due to a lack of authorization to comment.

Police earlier issued a statement saying the man was killed due to a “political discussion” and said a 59-year-old suspect named Edmilson Freire da Silva had been arrested. The suspect had been arrested before due to a domestic violence case, police said.

Non-profit organization Human Rights Watch said it regrets “one more assassination with an apparent political motivation” during the Brazilian electoral campaign. Ceara state is a stronghold for da Silva and his Workers’ Party.

“Candidates should vehemently condemn any act of violence and promote peaceful elections,” it said on Twitter

Neither Bolsonaro nor da Silva have commented on the incident.

Brazilian media reported that police in the state of Santa Catarina, a Bolsonaro stronghold, are investigating a second killing that could be linked to politics. On Saturday, a 34-year-old man died after being stabbed in Rio do Sul, a city of 72,000 residents.

Supporters of the president have said on social media channels that Hildor Henker was killed in a bar fight after he voiced his support for the far-right leader.

Da Silva, a leftist who governed from 2003 to 2010, is leading in virtually all polls against right-wing incumbent Jair Bolsonaro, who has insisted that the polls are wrong and that election fraud may rob him of the presidency.

Earlier in the campaign, a Bolsonaro backer killed a local official of da Silva’s Workers’ Party in the city of Foz de Iguacu and there have been less serious clashes between Bolsonaro and da Silva backers.

Workers’ Party lawmaker Paulo Guedes said on Twitter his car had been shot at three times by Bolsonaro supporters during a rally.

“How far does this hatred go?,” Guedes said on his social media channels.

Police in the city of Angra dos Reis near Rio de Janeiro said on Saturday that a woman had been hit on the head by a Bolsonaro supporter after expressing criticism of the president.

Both leading candidates have taken to wearing bulletproof vests for public appearances. Bolsonaro nearly died due to a stabbing by a mentally ill man in the 2018 campaign.

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