Alessandro Lisi, 35, was arrested in the Etobicoke area Tuesday night, although Toronto police would neither confirm nor deny Lisi was taken into custody, The Globe and Mail said Wednesday.
Lisi's lawyer, Domenic Basile, declined to comment.
The newspaper said no reason for the arrest was given.
Police have been investigating Lisi after two media outlets reported in May drug dealers had tried to sell an alleged video purportedly of Ford smoking crack cocaine.
Ford has questioned the existence of the video and has denied using crack.
"I can't comment on a video that I have never seen or does not exist," he said in May.
Toronto police have interviewed several former mayoral staffers about attempts to retrieve the alleged video, people close to the mayor's office told The Globe and Mail. Some of the questions police asked focused on Lisi, a regular late-night companion of Ford, who was known to drive the mayor to events even though he has no official role in the mayor's office, the sources said.
Ford hasn't answered questions about his relationship with Lisi, except to tell the Toronto Sun Lisi was "a great guy and straight as an arrow."
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