The driver - a 30-year-old born in Bergamo and of North African origin, who had moved to the province that includes Modena - attempted to flee after the car crashed into a shop window, Modena's mayor told broadcaster RaiNews24.
The incident occurred in the afternoon in Modena's historic centre, where the vehicle sped into a street in the old town.
The fleeing driver was stopped by some pedestrians, one of whom he attacked with a knife and slightly injured.
The driver was later arrested by police.
The driver was receiving treatment for psychiatric disorders, a source in the Italy's interior ministry said, without elaborating on the man's motivations.
Among the injured, four were in serious condition and two were airlifted to a hospital in Bologna, about 40km from Modena, the city's mayor, Massimo Mezzetti, told RaiNews24.
"It seems (the driver) deliberately drove onto the sidewalk, hitting several people," Mezzetti said.
The man who was stabbed by the driver told RaiNews24 he heard people falling and threw himself to the ground as the car approached.
He said the driver appeared to be under the influence of alcohol or drugs.
Authorities have not confirmed this.
"I express my solidarity with those who were injured and their families," Prime Minister Giorgia Meloni posted on social media platform X.
"What happened in Modena is extremely serious. I trust the person responsible will be held fully accountable for his actions," she added.
Matteo Salvini, leader of the anti-immigrant League Party, also posted on X, highlighting the driver's North African origins and calling him a "second-generation criminal".
with DPA
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