MONTREAL -- Officers from Quebec's anti-corruption squad raided nine locations including Montreal's city hall and six Montreal borough offices Tuesday afternoon.

The coordinated raid came down at about 4:20 p.m. by the Unité permanente anti-corruption, or UPAC, as some 125 police officers swooped in to locations throughout the island of Montreal.

It was all part of a two-year-old investigation related “allegations of breach of trust by a public officer, fraud and forgery document,” said UPAC spokesperson Anne-Laurence Frederick.

A news report said the new mayor, Michael Applebaum, and the man he recently replaced, Gerald Tremblay, were both among 25 people questioned by police. Spokespeople at the police squad and city hall did not confirm, or deny, that report.

Applebaum added some details later, at a 9:15 p.m. news scrum outside city hall. He confirmed meeting with police but said he was not a target of the probe -- only a participant.

"I'm not under investigation," Applebaum said. "I'm there to work with the police… This investigation has nothing to do with Michael Applebaum whatsoever. I want to be clear on that."

He did not elaborate on reports that the raids were related to the 2009 campaign financing of Union Montreal -- the long-ruling, now-crumbling municipal party Applebaum recently abandoned.

“What I can tell you is that I will give them my total collaboration in order to shed light on the questions they have or any dossiers they are looking at,” he said.

He said he wanted to avoid revealing details that might hamper the investigation.

But the mayor did say: "I ran a clean campaign. I raised money legally."

He also sought to downplay Tuesday's events, calling it "normal" that so many officers would be involved in a probe of this kind and that he would speak with them.

A number of arrests have already been made in connection with construction corruption, which is also the subject of the ongoing Charbonneau Commission.

The boroughs of Cote-des-Neiges-Notre-Dame-de-Grace, Saint-Leonard, Lachine, Verdun, Anjou and Saint-Laurent were raided. Union Montreal offices were also raided.

The Cote-des-Neiges-NDG borough was governed for years by Applebaum, the interim mayor of Montreal.

The doors of Montreal's city hall were locked at 4:20 p.m.

Project Montreal leader Richard Bergeron described how all elected officials were ordered to leave after an alarm sounded, and a voice over a loudspeaker ordered them out while investigators conduct their raids.

City hall workers also told to evacuate the building in an email sent by City Council President Harout Chitilian.

“Due to exceptional circumstances, we ask you leave your workstations and immediately leave Montreal city hall,” he writes, adding that “this shall continue until further notice.”

Outside city hall, Vision Montreal leader Louise Harel said she was stunned.

“This is certainly unheard of!” she said, adding that when she served as Minister of Municipal Affairs from 1998 to 2002, “There may have been some searches in cities, but never in a city like Montreal.”

It was a shock, said Bergeron.

“I am ashamed to see that this happened in the second largest city in Canada, but police know what they have to do and when they give you an order to leave the building, you leave the building. You don't discuss,” he said.

No one was arrested, but reports say of the 25 witnesses were interviewed by police, some are elected officials, former elected officials and service providers.

The investigation is ongoing.

Though it is the first time city hall has been raided as part of anti-corruption investigations, past city officials were targeted by UPAC and the Hammer Squad last May.

Eight people were arrested in connection with the Faubourg Contrecoeur construction project, including former executive committee president Frank Zampino and construction magnate Frank Zampino,former chairman of the housing board of Montreal, Martial Fillion, and a former political organizer Union Montreal, Bernard Trépanier.

With files from The Canadian Press.