The "what" was big news yesterday—dozens of arrests in connection with one of the world's biggest diamond robberies—and the "how" begins to emerge today: The investigation into February's $50 million Brussels airport jewel heist leaped forward when police found out that, soon after the theft, an organized-crime boss from southern France had turned up in Switzerland. The unnamed boss seems to have made the trip in order to help sell off the diamonds, and investigators were able to map him to others in the criminal network, the New York Times reports. The current count: 24 men between ages 30 and 50 nabbed via 40 raids in Belgium, along with another eight people in Switzerland and one person in France.
Investigators reportedly found nearly a third of the stolen diamonds in Geneva, along with $110,000 and several high-end cars; they also picked up thousands of dollars and a Porsche in France. Many of those arrested were middlemen, though at least one is suspected of having taken part in the heist itself. A Belgian prosecutor's spokesman wouldn't answer questions on whether airport staff might have been involved in the crime, the Times notes. (Read more Brussels stories.)