Senegalese community spokesman Pape Diaw speaks with Florence Mayor Dario Nardella during a demonstration Tuesday against racism and the killing of Senegalese street vendor Idy Diene. (Claudio Giovannini/EPA-EFE)

MILAN — On Monday morning, 53-year-old Idy Diene, a Senegalese man who had lived in Italy for 20 years, followed his typical routine: he took the train from Pontedèra, the small Tuscan town where he lived with his new wife, and headed to Florence, where he worked as a street vendor, selling tissues and lighters.

A devout Muslim, Diene was expected to show up at Florence’s central mosque for noon prayers. He did not. A half-hour earlier, he had been shot dead.

Diene's death has set Florence's African community on edge as it deals with rising racial resentment in Italy. Indeed, it was the second time in seven years that exactly such a tragedy struck Diene's family. His wife was the widow of his cousin, Samb Modu, who also worked as a street vendor in Florence and was murdered in 2011 by a far-right gunman. That attack, said Diye Ndiaye, the chairwoman of the association of Senegalese citizens in Florence, remains “an open wound.”

Diene's killing, carried out by a white man, has not been linked to racial hatred. The police told Italian news outlets that, for the moment, they are ruling out racial motivations. The shooter, they said, claimed that he originally planned to commit suicide but lost his nerve. Instead, he shot the first person he saw, hoping to be arrested.

But that explanation has not satisfied the local African community. A few hours after Diene's death, about 100 young Africans rallied in the city center to protest what they perceived as a racist attack. Diene’s widow, Kene Mbengue, told the daily newspaper La Repubblica that she believes her second husband's killing was a hate crime, as was her first husband's.

That anger boiled over at a Tuesday vigil for Diene attended by Florence's progressive mayor, Dario Nardella. After a flower pot was broken during Monday's demonstration, Nardella called the event a “violent protest.” His critics charged that he was paying far too much attention to the flower pot while the city ignored what they felt was a clear hate crime. At the vigil, some African protesters yelled that Nardella was a racist. Another protester, who was not Senegalese, spit in the mayor's face.

Ndiaye told The Washington Post that Nardella is generally well-respected by local Senegalese. His administration “has a good relationship with the Senegalese community,” she said, adding that Nardella was “very supportive” after the 2011 shooting.

Nardella told The Post that the city of Florence will act as plaintiff in the trial against Diene’s killer. He also refused to speculate about the motives behind the shooting, but said that “this is the moment of showing solidarity to the African community.”

“The point is that ... people are really scared right now,” Ndiaye said. She also refused to speculate about Diene's killing but said she is worried about “the general climate” for Africans in Italy.

Across the country, racial tension — and racist violence — is on the rise. Last month, another far-right gunman shot six African immigrants in the city of Macerata. And on Sunday night, as anti-immigration parties racked up huge gains in parliamentary elections, a mosque was torched in the northeastern city of Padova (the building was empty and nobody was injured).

“It’s not like we didn’t have hate crimes before,”  said Igiaba Scego, who studies the Afro-Italian community for the International Center for the Humanities and Social Change in Venice. “The difference now is that the people who won the elections are the same one who yell racist slogans.”