MONTREAL -- A senior Montreal police officer has been suspended after the force's provincial counterparts raided its headquarters in a case involving alleged fraud and breach of trust.

Montreal's police chief said earlier today the mixed investigative unit was acting on a complaint against his chief of staff, Imad Sawaya, when it executed a search warrant late Thursday.

Philippe Pichet told reporters an investigation into Sawaya took place in 2015 amid allegations regarding overtime and bonuses, but said the case was studied and no anomaly was found.

Pichet said he had the utmost confidence in Sawaya but that he would have to make a decision on his future.

Just hours later he announced in a terse statement that a senior member of his team was being suspended for an undetermined period.

The statement did not name Sawaya.

The police chief said the Montreal force is co-operating with the unit, which is comprised of members from various police forces.