Rock stars Bruce Springsteen and Sir Paul McCartney have been silenced after defying the sound curfew at Hard Rock Calling.
Sir Paul had joined Springsteen on stage at the end of the singer's headline slot in Hyde Park, London, but both stars found their microphones cut off before they could address the crowds.
Springsteen, known for his long performances, had been playing for more than three hours and had exceeded the curfew by half an hour.
After belting out hits such as Born In The USA and Because The Night, he welcomed Sir Paul to the stage to sing Beatles hits I Saw Her Standing There and Twist And Shout, but neither performer had the chance to thank the crowd, and had to leave the stage in silence.
Springsteen, who played with his E Street Band, had earlier invited Rage Against The Machine's Tom Morello on stage to perform two songs, and singer John Fogerty had joined him for one.
He delighted the crowds with his energetic set, and often left the stage to shake hands with audience members. At one point he rewarded a fan's loyalty by playing an obscure track from his back collection.
The singer spotted a man holding up a banner asking him to play the song Take 'Em As They Come, and listing the concerts around the world where he had requested it.
Holding up the banner on stage, Springsteen praised the "big investment" the fan had made to see him in places including Madrid and Paris, then said: "Tonight, my friend, this is your lucky night. You're going to hear this damn thing."
He added: "It's a completely obscure track I wrote for The River when I needed some rock songs."
On Sunday, singer Paul Simon takes to the stage, while last night 90s grunge band Soundgarden played.