In an ironic twist, U2 [ tickets ]'s free performance celebrating the 20th anniversary of the fall of the Berlin Wall has generated controversy over the construction of a security fence--which some are calling a wall--blocking fans from viewing the show.

Fans who gathered Thursday (11/5) in Berlin to see the free, four-song performance by U2 at the base of the famed Brandenburg Gate were upset to find that a more than six-foot high metal barrier, covered with a white tarp, had been installed to block the view of those without tickets. Ten thousand free tickets were distributed online for the event, which was being staged as part of the MTV Europe Music Awards.

"It's completely ridiculous that they are blocking the view," U2 fan Louis-Pierre Boily, 23, told the AP. "I thought it's a free show, but MTV probably wants people to watch it on TV to get their ratings up."

A statement released by MTV said the music network "wants to ensure that the 10,000 music fans expected to attend tonight's production enjoy a safe and happy experience," adding that the temporary security fence was placed around the site perimeter after consulting with the city and local police, as well as the event's promoters.

"Under no circumstances did MTV build a 'wall' of any kind in or around the U2 production site," the statement added.

U2 representatives have not commented on the matter.

Local politicians also were not impressed with the viewing obstacle. "It's a shame that a barrier has been set up. It's stopping many Berliners from hearing the concert," local parliament member Frank Henkel told the BBC.

"It would have been so much better if as many Berliners as possible could have taken part," he added.

The show was announced just a few days ago, with the allotted free tickets being snapped up within hours online. "It'll be an exciting spot to be in, 20 years almost to the day since the wall came down," U2 manager Paul McGuinness said in a statement last week. "Should be fun."

The band recently announced a new leg of North American dates next summer for its 360 tour. The trek, currently set to visit 12 cities, kicks off June 6 in Anaheim, CA.