The Wikimedia Foundation, a U.S. nonprofit that hosts Wikipedia, has banned seven mainland Chinese users from its websites and revoked administrator access for 12 others, in a case that was described by its vice president as “unprecedented in scope and nature.” Maggie Dennis, the Wikimedia’s vice president of community resilience and sustainability, announced the penalty in an email on Sept. 13 to Wikimedia members. She said the foundation made the decision after “long and deep investigations” into some members of the Wikimedians of Mainland China (WMC) user group. Dennis did not provide detailed explanations over what the 19 users had done, but only said that there was a “security risk” with “infiltration concerns.” For the 12 users who had administrator access, she appeared to suggest that they had engaged in or were connected to election canvassing. “We have also reached out to a number of other editors with explanations around …