Milan's police chief, Antonio de Iesu, has said police in the city had no intelligence or information to suggest that the Berlin lorry attack suspect was in the city.
Mr de Iesu said that Anis Amri appeared suspicious and was stopped as part of a routine patrol by two officers.
Mr de Iesu continued that the 24-year-old arrived at Milan's central station at around 1am local time, but was shot dead outside Sesto San Giovanni train station, 4.7 miles away, two hours later when he opened fire on police who asked to see his ID.
He added that police were suspicious of Amri and approached him because the station was closed.
Italian officials are trying to determine how Amri arrived at the piazza by Sesto San Giovanni train station as while some buses run at that hour, no trains, trams or metros do.
Mr de Iesu said Amri "surely passed through France," but he did not provide any more information about the suspect's travels, citing the ongoing investigation.
An unnamed Italian official said they are working to determine what contacts, if any, Amri had in Milan.
There is no evidence to suggest that Amri ever passed through Milan during his previous stay in Italy, during which he spent more than three years in prison.
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