Donald Trump is attacking a CNN anchor of colour for bringing up tweets the president launched against minority politicians and civil rights leader that were largely viewed as racist.He referred to journalist Don Lemon as “the dumbest man on television” for discussing the tweets at Tuesday night’s Democratic debates, adding, “I am ‘the least racist person in the world,’" appearing to quote his own previous claims about himself.The president found himself under siege in the latest round of Democratic 2020 primary debates on Tuesday evening, with Pete Buttigieg accusing him of pretending to be disabled to avoid service in the Vietnam War, and Elizabeth Warren saying he “disgraces the office of president every single day”. In further bad news for the president, California governor Gavin Newsom has signed a new bill into law that would make it mandatory for every presidential candidate to release five years of their tax returns or face being left off ballot papers in the state in November next year.Please allow a moment for our liveblog to load