(Note: strong language in paragraph eight)
Swedish fans initially mistook a women's rights protest for a spontaneous striptease on Tuesday when the Ukrainian Femen group staged a bare-breasted table-top demonstration against Euro 2012 in the capital Kiev.
But the whoops of delight turned to booing when Femen activists held up placards denouncing the European soccer championship and kicked Swedish fans' beer off tables in Kiev's fan zone.
The group, which carries out topless protests to highlight the growth of the sex industry in Ukraine, has targeted Euro 2012, which Ukraine is co-hosting with Poland and which it says feeds sex tourism.
In a statement, the group said one protest was successfully carried out on Tuesday in Kiev, but two other activists were quickly spotted and detained by police.
"The most recognizable activists, Alexandra Shevchenko and Inna Shevchenko, were seized in the vicinity, pushed out of the fan zone and badly beaten," the statement said.
But Femen activist Oksana Sachko climbed on to a table and danced with Swedish soccer supporters massed in blazing sunshine for the start of their team's Group D match against France which was to be televised on big screens.
There were initially whoops of delight from fans when Sachko, a 25-year-old icon painter and one of the group's main activists, took off her khaki T-shirt.
But when she revealed the words "Fuck Euro 2012" written across her torso and held up a placard with the same slogan they began to boo and jeer.
When a fan grabbed her by the arm, she lost balance and fell to the ground. Ukrainian security volunteers finally managed to carry her out of the zone and she was taken off by police.
"To be honest, if you see the guys here, if the girls show off topless it will just get positive attention. I am not really sure that they (Femen) got their message through," said one Swedish fan Christian.
"I think there may be some guys here who were just happy to see the topless girls and I don't think that was the intention by the girls," he said.
"The activists of Femen carried out a protest against the low-life fans in the fan zone of the Swedish national side. The activists climbed on to tables and began to kick away the cans of beer with which UEFA has generously lubricated the throats of football fanatics," the Femen statement said.
Ahead of Euro 2012, which began in Poland on June 8 and will end with a final in Kiev on July 1, the Femen group threatened a wave of actions to disrupt the tournament.
Its activists made two attempts to seize the tournament's Henri Delaunay trophy when it was on public display in various towns of Ukraine before the tournament opened.
(Additional reporting by Reuters TV; Writing By Richard Balmforth, editing by Ed Osmond)