A WestJet flight headed to Toronto made an unexpected landing in Thunder Bay, Ont. on Saturday after a passenger allegedly uttered a bomb threat.

The Boeing 737 aircraft travelling from Vancouver landed at Thunder Bay International Airport at about 5 p.m. ET.

Police ordered all 188 passengers off the plane to allow the Ontario provincial police bomb squad to search the aircraft. No explosives were discovered.

The diversion was allegedly triggered by comments made a 27-year-old Portuguese man with a history of mental health issues, said Thunder Bay Police Services in a statement issued Sunday.

No charges have been laid but police have held the man for a medical assessment.

Police in Thunder Bay said they expect that the man will be sent back to Portugal once his medical evaluation is complete.

Officials said the interrupted flight is expected to complete its journey to Toronto on Sunday afternoon.

The flight diversion occurred the same day various media outlets reported that another WestJet aircraft bound for Toronto from Vancouver made an emergency landing after the crew smelled smoke.