A Vatican whistle-blower who has accused Pope Francis of having covered up sexually abusive behaviour by an American cardinal stepped up his attack on Wednesday, speaking from a secret location. Archbishop Carlo Mario Vigano, a former Vatican ambassador to the US, has plunged the Catholic Church into crisis with allegations that the pope failed to act against Theodore McCarrick, a US cardinal, who was accused of sexually abusing young priests over decades. Cardinal McCarrick, the former archbishop of Washington, resigned in disgrace last month, becoming the first cardinal to step down since 1927. Archbishop Vigano, 77, released an 11-page document detailing the allegations at the weekend and called on Francis to resign. He then went underground amid reports that he feared for his safety. After days of silence he gave an interview, from an undisclosed location, to an Italian journalist, renewing his criticism of Francis’ papacy. Cardinal Theodore McCarrick resigned in disgrace in Ju...