Air Canada ground crews and baggage handlers have walked off the job at Pearson airport in Toronto late Thursday night, causing flight delays.

The job action began Thursday evening and left hundreds of passengers in limbo after they had to disembark from several flights already on the tarmac and head back to the terminal.

A spokesman for the airline confirmed late Thursday that a number of "ground handling" workers at the airport had engaged in an "illegal job action."

"The majority of employees continue to do their jobs and take care of our customers," Peter Fitzpatrick said in an email to CBC News. "It is too soon to say what if any effect this activity will have on our schedule, however it has not resulted in any cancellations at this point."

Greater Toronto Airports Authority spokesman Scott Armstrong said the workers walked off the job shortly after 10 p.m. ET and were holding a demonstration "on the curb" at Terminal 1.

The CBC's Redmond Shannon reported from the airport that the walkout followed an incident involving Labour Minister Lisa Raitt, who had been applauded sarcastically by some Air Canada workers as she walked through the airport earlier in the evening.

At least three workers were suspended by Air Canada, according to workers demonstrating outside the terminal, prompting the walkout.

By 1 a.m. Friday, the airport website had displayed seven Air Canada flight delays. Six were to Canadian destinations — St. John's, Edmonton, Calgary, Halifax, Winnipeg, Vancouver — and one international flight to Frankfurt, Germany.

"There's a three hour lineup to get a hotel," said Aaron Huizing, who had been flying back to Ottawa from the Dominican Republic. "There'll surely be just as long a wait once we get to the hotel. At this rate we won't get to sleep until morning anyway."

Air Canada has been plagued with labour troubles over the last year. The airline and its pilots and mechanics have been in a bitter contract feud that prompted the federal government to recently step in with legislation banning strikes or lockouts at the airline.

The government also used back-to-work legislation during Air Canada's contract dispute with customer service and sales staff last June.