Ford, who has repeatedly attacked the legitimacy of the probe and Bill Blair, wasted little time in criticizing the move, which puts provincial police in charge but leaves city investigators on the case.
"The damage has already been done," Ford said at city hall.
"The chief obviously is playing political games and it should have been done from the very beginning."
Earlier Wednesday, Blair released a letter he had written to OPP Commissioner Chris Lewis in which he laid out his reasons for asking his provincial colleagues for help.
"I am taking this step to avoid the distractions that have assumed such recent prominence," Blair wrote.
"The only public interest here is the continued investigation, without fear or favour, into evidence of possible criminality."
Ford has publicly accused Blair of wasting tax money with the investigation, and vociferously challenged the chief to arrest and charge him.
The mayor said he was not concerned at the possibility.
"Charged for what? For an empty vodka bottle or urinating in a park," Ford said Wednesday, repeating a similar line to one he said on Monday's "Jimmy Kimmel Live" TV show. "Which one?"
Blair, too, has gone public with comments critical of the mayor, most recently last week when he called Ford's profane rant against him videotaped in a city restaurant "disgusting" and "shameful."
The Toronto police investigation in question — dubbed "Project Brazen 2" — arose last spring out of a year-long guns, gangs and drugs probe.
It was during the initial probe that police uncovered a video showing Ford apparently smoking crack cocaine, and decided to investigate his activities.
Ford's friend Alexander (Sandro) Lisi was charged in the first investigation with drug offences, and later with extortion in relation to the "crack" video. The allegations have not been proven in court.
"We're always very concerned that nothing is said or done that could have any impact on current or future court proceedings," said Toronto police spokesman Mark Pugash.
"We'll always err on the side of caution."
Veteran Toronto homicide investigator, Det.-Sgt. Gary Giroux, will continue to lead the investigation, but will now answer to a senior provincial police officer rather than to senior city police officers.
The provincial inspector will have no direct involvement in the probe, but will be available for consultation or to offer advice, police said.
OPP Commissioner Chris Lewis said the change is "semantics" but said the investigative team will no longer report up a chain in Toronto police, ultimately to Blair.
"That removes the whole senior management team of the Toronto police and the chief from any involvement — or perception of involvement — in any decision-making around this case," Lewis said.
Blair wanted the public to be confident that there was no interference from the chief or other senior city officers, Lewis said, adding there was no indication any charges were imminent.
On Monday night, Ford attacked Blair during an appearance on the U.S. late-night talk show "Jimmy Kimmel Live."
"They follow me around for five months and came up empty-handed. I just want him to come clean with the taxpayers,'' Ford said. "It's all politics."
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