An Italian man has opened fire in two markets in central Florence, killing two Senegalese traders and injuring three others.
The attacker, 50-year-old Gianluca Casseri, belonged to a far-right group, Italian media said.
He killed two men and injured a third in Dalmazia Square before opening fire in San Lorenzo Square, wounding two.
Casseri was later found dead in an underground car-park, having turned the gun on himself, police said.
Italy's president, Giorgio Napolitano, denounced "this blind explosion of hatred" and called on Italian authorities and society to "combat in the bud every form of intolerance and to reaffirm the tradition of openness and solidarity in our country".
The mayor of Florence described the shooting spree as that of a deranged person acting alone.
"These are the actions of a lone killer - a lucid, mad and racist killer," Matteo Renzi said, adding that such behaviour was out of character for the city and had shocked it to its core.
Casseri is reported to have calmly got out of a car in Dalmazia Square and opened fire, killing the two Senegalese in the market, and injuring a third.
"I heard what I thought were fireworks but when I turned around I saw three men bleeding on the floor," a market trader who saw the attack told La Repubblica.
As shoppers and traders fled in panic, some people tried to pursue Casseri, but he escaped in his car.
Later he began firing at other Senegalese traders at a market in a second square near the city's cathedral - one of the city's largest - injuring two more people.
Dozens of Africans living in the city - many of whom make a living selling knick-knacks and fake designer bags to tourists - have marched through the city centre in protest at the killings, knocking over mopeds, bins and street signs.
A published author of science-fiction novels, Casseri is reported to have belonged to a far-right association called Casa Pound.
The group sought to distance itself from Casseri saying it did not support any type of violence.
Fabio Barsanti, a regional co-ordinator for the group, described Casseri as "lonely" and "living in his own world" but "not crazy".