The Stronger hitmaker stormed the stage at the fabled music event in Somerset, England and Britain's BBC network aired the show after the set U.K. watershed of 9pm, the cutoff for child-friendly TV.

Several viewers complained directly to the BBC and to regulatory body the Office of Communications (Ofcom), where bosses are investigating 47 complaints, but corporation chiefs have now defended the broadcast.

A statement posted on the BBC website reads, "We received complaints from some viewers who were unhappy with some of the language used by Kanye West during his headline set... The performance was broadcast after the watershed and clear warning notices were given that it may contain strong language - both at the start of the show and again, with a caption placed on screen just as Kanye's act started."