Iceland’s Prime Minister Sigmundur David Gunnlaugsson became the first major casualty of the Panama Papers revelations, stepping down on Tuesday after leaked files showed his wife owned an offshore firm with big claims on the country’s collapsed banks. The leaked documents from a Panamanian law firm that specializes in setting up offshore companies have shone a light on the finances of politicians and public figures from around the world, causing public outrage over how the powerful are able to hide money and avoid tax.