Police in the Polish capital on Saturday detained a man who climbed the top of a monument and reportedly threatened to blow himself up. Large numbers of police and special counterterrorism officers sealed off a large square where the man had shouted something through a megaphone for hours. The incident took place at Pilsudski Square, the site of the memorial to late President Lech Kaczynski and the dozens of other victims of a plane crash near Smolensk, Russia.