BRUSSELS (AP) -- Unlike the brilliant thieves in "Ocean's Eleven," it appears that those behind the clockwork-precision, $50 million diamond heist at Brussels Airport may not get a Hollywood ending.
After three months of virtual silence on the matter, authorities struck this week, detaining at least 31 people in a three-nation sweep and recovering so many diamonds from the loot Antwerp traders lost that they are still figuring out the exact value.
Officials said that among the people held in Belgium, France and Switzerland on Tuesday and Wednesday are some with violent criminal pasts; the one person held in France is believed to have been one of the robbers at the airport. The evidence seized includes large sums of cash, precious stones and luxury cars.
"It was a total surprise for us," said Caroline De Wolf of the Antwerp World Diamond Center, whose traders lost millions in the Feb. 18 heist. "But we were delighted when we heard."
Six to eight people were detained in Geneva, and 24 in and around Brussels. It was unclear exactly what roles each suspect may have played.
Some 250 policemen were involved in the dawn raid in the Belgian capital, and many of the two dozen suspects were being interrogated late Wednesday. It could take at least another day before it's clear how many will be placed under arrest, said Anja Bijnens, a spokeswoman for the prosecutor's office.
Perhaps the most important discovery was in Geneva of stones that could immediately be linked to the cache spirited away from the airport.
That theft ranks among the biggest diamond heists of recent times, and many liken it to the plot of the 2001 Vegas heist movie, "Ocean's Eleven," which stars George Clooney, Brad Pitt and Matt Damon, for its clinically clean execution.
"In Switzerland, we have found diamonds that we can already say are coming from the heist, and in Belgium large amounts of money have been found. And the investigation is still ongoing," said Jean-Marc Meilleur, a spokesman for the Brussels prosecutor's office. He said police had also found luxury cars.
Meilleur was scant on detail, yielding no clues as to how police got on the trail of the suspects.
In Geneva, prosecutors said in a statement that "a very large quantity of diamonds was seized" during the sweep "coming from the spectacular heist at Brussels airport." While Belgian authorities spoke of six detentions in Switzerland, Geneva prosecutors put it at eight, including a businessman and a lawyer.
The value of the diamonds recovered was still being estimated. It was unclear how many of the other stolen diamonds are still missing.
The Feb. 18 heist was stunning and brazen.
The stones from the global diamond center of Antwerp had been loaded on a plane bound for Zurich when robbers, dressed in dark police clothing and hoods, drove through a hole they had cut in the airport fence in two black cars with blue police lights flashing.
They drove onto the tarmac, approached the plane, brandished machine guns, offloaded the diamonds, then left in an operation that barely took five minutes. Later that night, investigators found the charred remains of a van most likely used in the heist.
Despite this week's developments, De Wolf of the Antwerp World Diamond Center said that a full resolution could still be some time off.
"When they were stolen, the diamonds were all in different parcels. Maybe now they have all been mixed up," De Wolf said. "You need quite a bit of expertise to check them all -- size, color, purity. It doesn't happen in one-two-three."
Associated Press writer Frank Jordans contributed from Berlin.
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