Thousands of passengers faced long waits at Vancouver's International Airport on Sunday as security staff searched for a man seen bypassing pre-board screening.

The man, who was carrying a backpack, left undetected on an Air Canada flight for Toronto, said Jacqueline Bannister, spokeswoman for the Canadian Air Transport Security Authority. Thousands of domestic passengers were delayed by the security breach at Vancouver International Airport.
Meanwhile, thousands of domestic travellers who had already been cleared through to their gates � including people who were already on aircraft � were moved back to an unsecured part of the terminal.

After a security sweep, passengers had to line up and be checked through again. The shutdown, which lasted about an hour, delayed most flights leaving Vancouver. Police stopped the man for questionning at the Toronto airport, Bannister said. She said he likely missed security screening by mistake and might not have understood which lineup he was supposed to wait in.

No charges are expected in the incident.