It follows reports from Los Angeles on August 22, where some fans said the 69-year-old appeared unsteady on his feet. The rock icon has been in frail health since undergoing heart bypass surgery and later suffering a hematoma in 2013.

Motorhead moved to reassure supporters that the problem was caused by the city's altitude. They said: "The people are great, but the air is just too thin. The high altitude makes it difficult for breathing, and that's what happened with Lemmy tonight in Salt Lake City.