Councillor Doug Ford has called the police to the mayor's office, saying that someone has stolen "confidential" information.
Ford told CP24 that he believes someone has gained access to Toronto Mayor Rob Ford's contact list, which he said is only accessible to people in the office.
The mayor and each city councillor has his or her own contact list stored on their computer that is only accessible to that person, Doug Ford said.
The only people who would have access to the list other than the computer's user are members of the city's IT department, Ford said.
Ford said he thinks that mayoral candidate Karen Stintz has access to private email lists as a result of the theft. He said he's been contacted by people through email and over the phone, asking how Stintz got their contact information.
Stintz's press secretary Lauren Souch said in a statement that Stintz will not speak to the media about the allegations, and added that there are people currently supporting the Stintz campaign who have supported other candidates in the past.
Souch said that the campaign accepts contact lists from its supporters, but made no reference to the data from the Ford campaign.
A member of Stintz's campaign office later told CTV Toronto's Naomi Parness that the issue had been addressed and all email addresses have been removed from the database.
Ford said he has contacted the integrity commissioner, and an investigation will be launched. He added that he's handed all the information he has over to police.
"That's a very serious concern when a breach of security has happened," Ford told reporters outside of the mayor's office. "We're going to find out who extracted the information"
Toronto police confirmed to CTV Toronto that they have been to City Hall, and will decide if they will launch a criminal investigation when the information gathered from Doug Ford has been assessed.
Rob Ford has been away from his office since May 30, when he announced he was taking an immediate leave of absence to seek professional help for an alcohol abuse problem.
He is expected to return to City Hall on the afternoon of June 30.