Radical feminist group Femen has had two of its Facebook pages blocked by the social networking site because of nudity.
The Facebook censors went into action because of the large number of images of Femen activists taking part in topless demonstrations.
"The formal reason for the closure of the platforms is preposterous - they are accusing us of spreading pornography and promoting prostitution." Femen said. "Zuckerberg: Femen is not pornography."
Both Femen's main page and its French offshoot were taken down. Together, the two accounts have more than 170,000 followers, Femen said.
The accounts of some other branches, such as Femen Germany and Femen Tunisia, were spared the Facebook axe but activists' nipples were covered or blurred.
Femen has appealed against the decision and demanded that Facebook "return [to] the women's revolution its main mouthpiece".
Facebook said it had not accused the group's page of distributing pornography and promoting prostitution but said the pages had violated site rules.
"The Ukrainian Femen page was removed for violating our rules," a spokesperson for the company said.
"We have a very clear policy on nudity and the administrators of the page in question will have received multiple warnings that content on their page broke our rules. This is a rule that we apply equally and globally.
"At Facebook we believe users should have the ability to express their opinions, and we don't typically take down content, groups or pages that speak out against countries, religions, political entities or ideas."
Earlier in June, 20,000 people signed an online petition demanding that the social media site reverse its policy after the company took down pictures of mastectomy scars posted on two pages campaigning to raise awareness on breast-cancer.
Femen rose to fame with demonstrations in favour of women's rights and democracy around the world, including topless marches in Paris and an ambush of Silvio Berlusconi as he arrived to cast his vote in the general election in Italy in February.
The last stunt of the Ukrainian women's group was a topless attack by three Belgian activists on Tunisian prime minister Ali Larayedh in Brussels.
Another three Femen members were jailed in Tunisia earlier this month for indecency and attacking public morals after staging a topless demonstration in support of local activist Amina Tyler, who is detained on separate charges.