Brazen robbers were able to make off with $50 million worth of diamonds in a daring Brussels airport heist, but they held onto their riches for less than three months. In a cross-border operation, police have arrested 31 people in connection with the heist—one of the world's biggest diamond robberies—and have also recovered some of the diamonds and quite a bit of cash, the BBC reports. The first suspect was arrested in France yesterday, followed by six more in Switzerland, and 24 near Brussels in raids this morning involving 200 police officers, AFP reports. (More Brussels stories.)