By DAILY MAIL REPORTER
Clash: Security staff and members of direct action group Art Uncut tussle over a 20ft balloon during last night's performance
Violent scenes broke out in the crowd at U2's long-awaited Glastonbury debut last night as a protest against the Irish band's tax status was foiled by security guards.
As Bono and his bandmates took to the Pyramid Stage, activists from direct action group Art Uncut inflated a 20ft balloon emblazoned with the message 'U Pay Your Tax 2'.
But as the campaigners tried to release the balloon over the 50,000-strong crowd, a team of ten security guards wrestled them to the ground before deflating the balloon and taking it away.
The intervention by security after U2's opening song Until The End Of The World sparked angry clashes with 30 or more protesters.
One security guard told a photographer to 'go away', adding: 'If you are press, I'll have you.'
Several protesters were pinned against a fence near the Pyramid Stage after attempting to hold on to the balloon. There were no arrests.
Facing the music: U2 frontman Bono sang through the protest
One of the campaign group members said: 'That was totally over the top. He threatened to hit me.'
Another said: 'Political activism used to belong at Glastonbury. This was all going to be completely peaceful.'
A handful of U2 fans looked on open-mouthed and booed as the security guards swooped.
Gary Noble, 45, from Eastbourne, said: 'It was all a bit shocking. I love U2 but I think everyone should pay their taxes. The campaigners have a right to voice their opinion.'
U2 rattled on through their set of smash hits, with the only inconvenience for Bono being the rain fogging up his trademark sunglasses.
Getting the message across: The 20ft balloon created by protest group Art Uncut
Art Uncut had been hoping to spark debate around big-earning stars' duty to pay taxes in their native country.
Campaigner Charlie Dewar said: 'U2's multi million-euro tax dodge is depriving the Irish people at a time when they desperately need income to offset the Irish government's savage austerity programme.
Pop music: The giant balloon eventually burst after being seized by security officials
'Tax nestling in the band's bank account should be helping to keep open the hospitals, schools and libraries that are closing all over Ireland.
'Bono is well-known for his anti-poverty campaigning but Art Uncut is accusing him of hypocrisy.'
The opening night of major acts, which saw revellers drenched in rain for the third day running, proved to be one of political activism.
Morrissey had drawn cheers from the audience after calling Prime Minister David Cameron a 'silly twit' for opposing an outright ban on wild animals in circuses.
Rocking and rolling: The security team eventually managed to take the balloon away
Introducing the classic Smiths song Meat Is Murder, he hailed MPs' support this week for a prohibition.
The singer condemned Mr Cameron over claims he tried to bully one MP into dropping the plans, saying: 'What a silly twit.'
Radiohead were unveiled as last night's secret act on the Park stage, with frontman Thom Yorke telling fans: 'We're here to get in free.'
He added: 'We asked Emily Eavis if we could get in free and she said, 'Will you play?
'We like it here as much as you do.'
Close to The Edge: The protesters attempt to lift the balloon near the stage where U2 were performing
Uplifting: One protester lunges at a security guard while spectators look on
The relentless rain has seen Worthy Farm become Britain's biggest mudbath - but the weather will dry up tomorrow, forecasters said.
Among the 170,000-strong crowd on the 900-acre site were Wayne and Coleen Rooney.
The footballer and his wife sparked a media frenzy as they joined the party.
Despite the rain and dark clouds, Rooney wore dark glasses as the couple walked arm in arm wearing matching Hunter boots.
The show must go on: While U2 managed to complete their performance, the band's fans were shocked at the way the protest was put down
Rooney, who had his hood up after recently having a hair transplant, was seemingly in good spirits after returning from a break in Barbados to travel to Somerset.
The 25-year-olds were believed have shunned a tent in favour of VIP treatment in a top-of-the range motorhome.
Moroccan act Master Musicians of Jouhouka and rapper Chipmunk got proceedings under way.
But the showers came back with a vengeance when the likes of rappers Wu-Tang Clan came on stage in the afternoon.
Marc Argent, 32, from Street, Somerset, was one of hundreds gathered around the Pyramid to perform a welly stomp dance in the quagmire.
He said: 'It's great to see it all under way. It's muddy but it is still magical.'
Forecasters say that today and tomorrow should be largely dry, with temperatures possibly topping 25C (77F).
Coldplay and Beyonce are the remaining headliners.
U2 - Glastonbury 2011 Part One - Even Better Than The Real Thing - The Fly - HD
U2 - Glastonbury 2011 Part Two - Mysterious Ways - Until The End Of The World - HD
U2 - Glastonbury 2011 - Part Three - One - Where The Streets Have No Name - I Will Follow - HD
U2 - Glastonbury 2011 - Part Four - I Still Haven't Found What I'm Looking For - Stay
U2 - Glastonbury 2011 - Part Five - Beautiful Day - Elevation - HD
U2 - Glastonbury 2011 - Part Six - Get On Your Boots - Vertigo - HD