[Update 9:38 p.m. ET] The security issue was a bomb threat that had been called in at 10:43 a.m. (1:43 p.m. ET), Cpl. Sherrdean Turley of the Royal Canadian Mounted Police told reporters outside the airport.
[Update 8:28 p.m. ET] The plane, which was coming from Hong Kong, landed safely in Vancouver at 1:35 p.m. PT (4:35 p.m. ET), said Alisa Gloag, a spokeswoman for the Vancouver Airport Authority.
Passengers were deplaned and the aircraft was being towed to another area for inspection, said Gloag, who did not have information about how the threat was reported.
The Royal Canadian Mounted Police is investigating, Gloag said.
[Posted 8:09 p.m. ET] Two CF-18 Hornets were scrambled from a Canadian military base Saturday to escort a Cathay Pacific Airways flight into Vancouver's airport, according to an official with the North American Aerospace Defense Command.
The action was taken in response to a "potential threat" to the flight, Maj. Holly Apostoliuk of NORAD told CNN.
The plane was escorted to the airport and directed to a restricted area.
No further details were immediately available.
– CNN's Greg Morrison and Nick Valencia contributed to this report.