Police on Wednesday were trying to find who left two pig heads stuck on metal stakes outside the site of a planned Islamic school in Australia's largest city. State ethnic relations officials described the act as a "display of hatred" after a passer-by reported the heads placed near an Australian flag at an empty block in Camden, a suburb in Sydney's Southwest, on Wednesday. Detective Inspector Paul Albury said police were seeking information about a person who had used a citizen's band radio to claim responsibility for the pig heads. Pigs are considered unclean by Muslims. Jeremy Bingham, a spokesman for the Quranic Society that is planning to build the school, said the incident was "a bit sad, frankly" and that he did not think it was representative of the feelings of most people in Camden.