It was after 6 pm on Thursday that the crime occurred.
Three people are said to be seriously injured and one is said to have been taken to hospital by helicopter.
However, it is unclear how seriously injured Pablo Marì is.
Mari who is currently on loan to Serie A club Monza from Arsenal.
- Now that we are far away, we are calmer but we were really terrified, we didn't understand what happened, we saw people running away in tears, says a girl who was in the shopping center when the attack took place, according to the Italian TV channel RAI.
The perpetrator, who is in his 50s, was arrested by police at the scene.
The motive is currently unclear, but according to the police, it is not an act of terrorism.
The text is updated.