A bomb threat forced the cancellation of the opening night of the Stratford Festival on Monday evening and prompted an evacuation of as many as 2,000 people from the Festival Theatre.

Police in Stratford, Ont., say they were called at approximately 6:45 p.m. about explosives being placed at the festival.

Staff at the festival were immediately advised, police said. As many as 1,830 theatregoers at the Festival Theatre were affected along with actors and staff, said festival spokesperson Ann Swerdfager. The nearby Avon Theatre was also ordered evacuated, though few if any people would have been inside.

It's the first time in the festival's history that opening night has been cancelled, Swerdfager said.

As of Monday night, police were still advising the public to stay away from the festival and the Upper Queen's area near the Avon Theatre while police search the grounds. How long that will take is not yet known, organizers say.

We're saddened to announce that there was a bomb threat made against a Festival Theatre tonight. To ensure the safety of our patrons and staff we have canceled the Opening of The Tempest. All ticket buyers will be contacted and reimbursed by us. —@stratfest The festival was to launch with a performance of Shakespeare's The Tempest by director Antoni Cimolino. In a tweet, festival organizers said they were "saddened" by news of the threat.

"I am sitting with Martha Henry who is holding Prospero's staff," Cimoloni said in a statement. "She will work her magic soon."

Henry, an early graduate of the National Theatre School of Canada, made her Stratford debut as Miranda in a 1962 production of The Tempest. This year she was set to play the role of Prospero, a role usually reserved for men.

'This is a first'

Theatre reviewer Keith Tomasek had just arrived in Stratford when he saw local police cars blocking access to the theatre.

"There were just hundreds of people all dressed up for a gala opening night with literally nowhere to go," he said.

Al Tucker, 75, was at the festival with his wife and friends. He had been in the theatre looking forward to the opening night production of The Tempest when police officers told theatregoers to leave (Al Tucker) Theatregoers were told there was some sort of security threat and exited "very calmly," he said.

"There was never any sign of panic. Cars, limousines that were approaching the theatre, they had to be turned back. People had made big plans for the evening and everyone was very calm for sure."

Tomasek said he's never seen an opening night shut down because of a threat.

"This is a first for me."

'Everybody out'

Al Tucker, 75, was at the festival with this wife and friends. They had just made their way to the balcony of the Festival Theatre, he said, when police yelled, "Everybody out!"

"It's very disconcerting, but with all the things going on around us in the world, we're not as surprised as we might have, should have been," he said.

Tucker has been going to the theatre for about 20 years.

"It's a real blow," he said. "I just hope it doesn't have a lasting impact on the theatre."

Organizers of the festival said ticket buyers will be reimbursed and that performances will proceed Tuesday — with added security.