(BRUSSELS) -- In a brazen heist right out of the movies, thieves drove onto Belgium's airport tarmac on Monday night and stole more than $50 million of diamonds from a plane without firing a single shot.
It took them fewer than five minutes to cut through an airport fence, drive up to a Helvetic jet in cars with flashing lights, hold up the pilot and security officials on the plane, and take 120 packages full of rough and cut stones, according to the Belgium prosecutor's office. The men carried submachine guns and were dressed in police uniforms.
"They forced open the fence between two construction sites, they made a hole, they went on the tarmac and they escaped through the same hole in the fence," the prosecutor's spokeswoman, Ine Vanwymersch, told reporters in Belgium.
The heist is one of the largest thefts in history and will raise serious questions about whether the thieves were tipped off to the location of the jewels by an insider, and how they could so easily drive onto the tarmac in a major European capital.
"It's quite remarkable that you can even get to the tarmac in [Brussels airport], with two vehicles and eight armed people," Caroline De Wolf, a spokeswoman for the Antwerp Diamond Centre, which promotes the Belgian diamond business, told Belgian TV. "That it's possible to get the goods out of the aircraft. This is unacceptable."
Police say they are still searching for clues. They found a burned out car -- presumably one of the vehicles used in the theft -- but have announced no other leads.
Belgium is one of the world's leading diamond centers and hasn't suffered as serious a theft as this since 2003, when thieves stole approximately $100 million of stones, jewels and gold from the Diamond Centre itself in Antwerp. Local media report that security has been beefed up since that attack, but on Tuesday, the airport could not explain why it was so vulnerable.
"We abide by the most stringent rules," airport spokesman Jan Van Der Crujsse told reporters.
Usually, transporting valuables on a plane is seen as safer than using cars or trucks, since a plane is always kept within the confines of an airport.
The plane, bound for Zurich and operated by Swiss airlines, was ready to leave when the robbery occurred. It was subsequently cancelled, the airline said.
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