Italian kills two, wounds three, before shooting himself
Senegalese community march in protest13 December, 18:31
He then drove to the San Lorenzo area, site of the popular market of the same name in the historic centre, and shot and wounded two others there before killing himself, police said.
"Do not tell us that he was crazy because if he was, he would have killed both blacks and whites," said the Senegalese who gathered in San Lorenzo after the shooting.
Casseri was described as a right-wing writer from Pistoia, a small town 30 kms west of Florence.
He co-authored an historical novel about a magician, mathematician and alchemist called La Chiave del Caos (The Key to Chaos) with Enrico Rulli and he was described as an introvert.
Casseri's book was published last year and he was well-known in Tuscany as he had appeared at a number of book presentation.
The local Senegalese community formed a procession led by leader Pap Diaw immediately after the shootings and marched to the office of the city prefect, Paolo Padoin.
Padoin was joined by Florence Mayor Matteo Renzi and Tuscany Governor Enrico Rossi.
The honorary consul for Senegal, Erando Stefani, said: "There is great loss and great pain but we will proceed with discretion".
When police arrived at San Lorenzo they shot at Casseri's car but failed to wound him.
The market was immediately evacuated and a police officer gave chase but as he got closer to Casseri, the killer drew his pistol and shot himself in the throat.