MONTREAL--The day after a once-mighty mayor was arrested in his own city and accused of being a gangster, aggressive questioning shifted toward local police.

The longtime police chief of Laval, the third-largest city in Quebec, found himself on the defensive Friday over why he never smelled anything fishy about his old boss, Gilles Vaillancourt.

The former mayor, whose 23-year reign in the city earned him the moniker the "Monarch of Laval," was smacked with a dozen charges, two of which are gangsterism-related.

One of those charges carries, in theory, a possible life sentence and is the most severe of the dozen charges against him.

But the top police officer, who reported to Vaillancourt for a decade and a half, told the 98.5 radio station Friday that he never noticed anything suspicious.

Jean-Pierre Gariepy insisted he never received any information that Vaillancourt, or any city officials, were involved in illegal activity.

"No, never -- never, never, never," Gariepy responded in an interview on the popular Montreal station.

"I worked with (Mr. Vaillancourt's) good side. A dark side, in which he (allegedly) worked in collusion with individuals to put money in their pockets -- (city officials) didn't highlight that for me."

Vaillancourt is among 37 people facing a long list of charges. Laval's city manager and its head of engineering appeared in handcuffs before a judge Thursday, alongside the ex-mayor.

Quebec's anti-corruption unit alleges the suspects were part of a network that illegally diverted money from public construction projects.

Gariepy confirmed in the radio interview a previous media report that the mayor was planning to move into the same condo building as him.

In addition to that, he addressed the fact that the police headquarters were housed in the same building as the offices of Dessau Inc. -- an engineering firm implicated in the controversy. One of Dessau's senior executives was arrested this week.

The police chief admitted Friday that living in the same building as the mayor -- and working in the same building as Dessau -- had been cause for concern.

"I found it inappropriate that a police headquarters was in a building that belonged to engineers that have dealings with the city," Gariepy said.

"That doesn't make sense."

He said he expressed those concerns to Vaillancourt, but the decision about the police headquarters ultimately fell to elected officials.

As for living in the same condo tower as Vaillancourt, Gariepy insisted he probably would have left the building if the mayor had ultimately decided to move in.

"It's not comfortable for a police chief to be close, to live close, to elected officials," he said.

"It's not good, it's not desirable."

Gariepy, who announced earlier this year that he would retire at the end of 2013, said he never investigated Vaillancourt or any other city officials.

He told the interviewer he had heard "hearsay" that corruption and collusion were present in Laval.

There had actually been media reports dating back several years -- which Vaillancourt aggressively denied -- accusing him of improper cash dealings.

The veteran police officer said he would have turned over any credible information about Vaillancourt or elected officials to provincial police.

But he insisted he never saw any credible evidence.

Gariepy said that just because Vaillancourt was arrested, as were others he knows from working in the city, doesn't mean he collaborated with them or closed his eyes to any wrongdoing.

"It's unfortunate that you have this opinion of me," he said, as he defended himself from pointed questions by the radio interviewer.

"I always did my work honestly. You can ask everybody in my organization."

Vaillancourt, 72, resigned as mayor in November amid allegations of corruption.

After his arraignment Thursday, Vaillancourt told journalists outside the courthouse that he was innocent and intended to fight the charges.