A man killed himself with a bomb outside Brazil’s supreme court after trying to enter the building on Wednesday, officials have said, stirring security concerns before the country hosts global leaders from the Group of 20 major economies. The blasts come five days before the G20 heads of state meet in Rio de Janeiro, followed by a state visit to the capital Brasília by Chinese President Xi Jinping. The first of two explosions went off on Wednesday evening in a parking lot near the court building and a second blast came seconds later in front of the court, where the