The opening show of the Stratford Festival’s 2018 season was cancelled abruptly Monday evening due to a bomb threat against the event.

Startford police say around 6:45 p.m. they received a call that explosives had been placed at the festival.

The Festival Theatre and Avon Theatre were evacuated as a result.

Police say officers remain on scene conducting searches for suspicious items or packages.

We are at @stratfest opening night - police are here & everyone is being evacuated from the theatre. Show cancelled. We are hearing there may have been a bomb threat. pic.twitter.com/sYef2GS8RY — Tina Yazdani (@TinaYazdani) May 28, 2018

A performance of William Shakespeare’s The Tempest had been scheduled to kick off the season. Stratford’s production of The Tempest is being directed by Antoni Cimolino, the festival’s artistic director. More than 1,800 people were in attendance for the show.

We are waiting to speak with police- in the meantime the hundreds of people that were here for @stratfest opening night have been told to clear the area. pic.twitter.com/Wc8TWfW8Ly — Tina Yazdani (@TinaYazdani) May 28, 2018

Festival organizers say all ticket buyers from Monday night will be contacted and reimbursed.

They also say all of Tuesday’s performances will go on as scheduled with increased security.