The SSPX has fired Bp. Richard Williamson from his post as head of a seminary in Argentina because of his Holocaust denial. The Pope had demanded that Williamson recant his views if he wished to continue his service to the Church. The SSPX, a fringe group by any measure, has tried to distance themselves from Williamson on the Holocaust, saying that his opinions were private beliefs and did not represent the organization as whole. Unfortunately, other opinions of Williamson -- misogyny, Islamophobia, some conspiracy involving Oklahoma City bombing, etc., etc. -- do apparently represent the SSPX, though they are doing their best to hide it by scrubbing their website of his writings.
They haven't finished scrubbing yet. A picture of Williamson can be found on the top right of the page, here.