A zoo in China has denied allegations that its bears are actually humans wearing elaborate costumes after images of the animals standing up on two legs went viral online. The Hangzhou Zoo in eastern China explained on its social media account on Monday that sun bears from Malaysia are smaller and look different to other ursine species, but that they are definitely real animals and not people. “Because of the way they stand, some people online question whether they are ‘humans in disguise,’” the Hangzhou Daily newspaper reported. An employee at the zoo told The Associated Press that visits were being arranged for journalists to see the bears on Monday. Other zoos have previously faced allegations of dyeing dogs’ fur to make them look like wolves and attempting to pass off painted donkeys as zebras.