Belgian police arrested Saturday dozens of demonstrators at NATO headquarters in Brussels as peace activists tried to enter its grounds, according to DPA. A Belgian peace initiative had called the protest under the motto "NATO game over" to prompt a debate on the alliance's role in the world. They put the number of demonstrators at around 700. Huge numbers of police took up positions around NATO's headquarters early Saturday. According to Vredesactie, more than 100 demonstrators had been arrested by Saturday afternoon. "Around 50 to 70 people managed to get inside the grounds, but were gathered up immediately. The others were arrested when they came too close to the fence," a spokesman said. Police did not put a figure on those arrested.