A WestJet flight that was forced to turn around after the crew spotted smoke in the cabin and cockpit has now landed safely at the Calgary airport.

WestJet Flight 1402 to Phoenix left the Calgary International Airport at 10:54 a.m. MT.

The flight crew declared an emergency after seeing the smoke and turned back to the airport, WestJet spokesman Robert Palmer said in an email to CBC News.

The fire department had responded with "multiple apparatus," spokesperson Carol Henke said.

The declaration of emergency was precautionary and did not necessarily mean the plane was ever in danger, Palmer said.

"The declaration does two things: it establishes priority landing and ensures the availability of emergency vehicles if they're needed," he said.