A WestJet flight from Vancouver to Toronto was diverted to Calgary last night after yet another threat.

It was the third "hoax" involving a bomb scare and the fourth threat overall against the airline in the past five days.

"Yes, we've been hit again," said WestJet spokesman Robert Palmer.

We believe the threat against <a href="https://twitter.com/hashtag/WS722?src=hash">#WS722</a> is a hoax. We diverted the flight out of an abundance of caution. —@WestJet

He confirmed WestJet Flight 722 took off from Vancouver at 5:14 p.m. PT Wednesday. The airplane landed safely in Calgary just before 8 p.m. MT.

The Boeing 737-700 was carrying 30 passengers and five crew members. The airline tweeted at about 8:30 p.m. MT that everyone was exiting the plane by mobile stairs.

Passenger Kyle Raymond tweeted to the CBC's Stephanie Wiebe that at least one fire truck was waiting nearby as the plane landed.

He said it was several minutes before the stairs were put in place to allow the passengers off.

<a href="https://twitter.com/StephWiebeCBC">@StephWiebeCBC</a> <a href="https://twitter.com/learaymond">@learaymond</a> the stairs are coming. I feel like Sandra Bullock in a very boring air version of Speed! <a href="http://t.co/oPf59YSK5g">pic.twitter.com/oPf59YSK5g</a> —@mrkyleraymond

WestJet says all flight 722 passengers were found seats on Toronto-bound flights later Wednesday evening.

The Calgary-based airline released a statement late Wednesday after what it termed "yet another hoax."

4 false threats in 5 days

"We understand and appreciate that four false threats in five days is generating a great deal of interest and unfortunately, rumour and speculation," the statement read.

"We will not comment on these rumours nor will we share information about how we handle with these incidents, for obvious reasons. We will continue to work closely with law enforcement to find those responsible. Safety remains our top priority and we will continue to be vigilant to keep our guests and our crews safe."

A previous threat was made on Tuesday night against Flight 323 from Toronto to Saskatoon. It landed safely at John Diefenbaker airport and all 113 passengers and five crew members were able to leave the aircraft safely using the stairs.

That wasn't the case Monday night when six passengers were injured during an emergency evacuation of a WestJet flight in Winnipeg. The Boeing 737-700 was about an hour and a half into its flight from Edmonton to Toronto when it made its emergency landing after an unspecified threat.

On June 27, a flight from Halifax to Edmonton was diverted to Saskatoon after an airport official in Kincardine, Ont., received a bomb threat. No explosives were found that time either, but the incident created flight delays in Saskatoon.

Air Canada and the St. John's Airport were affected last week, with a bomb threat the night of June 25 that led to an evacuation of airport buildings until safety was ensured.