Montreal - A man in his 30s was killed when an outdoor stage raised in a Toronto park for a concert of the British group Radiohead collapsed, police said on Saturday.
"Shortly after 16:00, a partial piece of stage at Downsview Park collapsed," a Toronto police spokesperson said. "There is one person deceased."
Three other people were injured, including a man in his 40s who was hospitalised.
The accident struck at Downsview Park about three and-a-half hours before the show was to start.
The concert was cancelled and officials opened a probe into the cause of the accident. Contrary to early speculation, there were no strong gusts of wind at the time the stage collapsed.
Police said they would not release the identity of the deceased until his family was informed.
The victims were all part of a team installing projectors and speakers on the stage and on the metal scaffolding above the stage.
Police said that the accident took place one hour before ticketholders were allowed to enter the grounds - but could have been much worse had a crowd been there and panicked.
Radiohead posted a message on Twitter saying that: "Due to unforeseen circumstances tonight's (show) at Downsview Park has been cancelled. Fans are advised not to make their way to the venue."
According to Radiohead's official website, the Toronto concert was sold out. Downsview Park can accommodate up to 40 000 spectators.