Investigators combed through the wreckage of a Toronto stage yesterday to determine what caused the structure to come crashing down ahead of a Radiohead concert, killing the band's drum technician and injuring three other crew members.

The British band said it was devastated over the death of Scott Johnson who was trapped under the rubble and pronounced dead at the scene.

Toronto Police spokesman Tony Vella said a 45-year-old man hospitalized with a head injury was improving and his life was not in danger.

The other two crew members were treated at the scene.