A suspect is in custody after a US United Airlines flight from Anchorage, Alaska to Denver, Colo., was diverted early Saturday morning to Canada's Vancouver International Airport because of "security concerns," CBC News reported.

"There was a legitimate security concern on board the flight and we do have a male in custody at this time," said Cpl. Dennis Hwang of the RCMP in Richmond, B.C.

United Airlines flight 1104 departed Anchorage a little before midnight, and was set to land in Denver shortly after 6 am, local time. It landed in Vancouver shortly after 4 am PT. There were no injuries.

The spokesperson wouldn't elaborate on the nature of the security concerns, referring questions to the RCMP.

Five ambulances were called to the airport and remained on the scene as of 7.30 am PT, said a BC Ambulance spokesperson

In a statement, a United Airlines spokesperson said the Boeing 737 was carrying 131 passengers and a crew of six.

The statement said the airline is working to re-book the passengers on other flights and is "co-operating with the authorities."

There has been no impact to operations at the Vancouver International Airport.