According to the Associated Press, Radiohead canceled a scheduled performance at Toronto's Downsview Park this weekend when a stage collapsed whiole it was being prepared for the show.At least three people were injured in the accident, and a stage tech was killed, according to the report.  SUmmer appears to be the season for stage collapses, as last summer saw dozens injured at a Sugarland concert in Indiana, three people died at a festival in Belgium, and eight people were hurt at a stage collapse before a Cheap Trick show in Ottowa last year.