(CNN) -- Eight masked thieves stole $50 million in rough and polished diamonds in a lightning-fast heist Monday at Brussels Airport, the Antwerp World Diamond Centre said Tuesday.
The stones were en route from Antwerp, Belgium, to Zurich, Switzerland, a spokesman for the diamond center said, citing police.
Police told the diamond center that the robbers, who used two vehicles, breached a security gate when the goods were already on an aircraft.
Jan Van der Cruysse, a spokesman for Brussels Airport, told CNN that it took the thieves only three minutes to rob the cargo hold and that they left the scene minutes later.
He said the robbers arrived in two cars, breached the gate, sped to the airplane and escaped through the same breach.
They were heavily armed, but no shots were fired, he said, adding that it all looked well-planned.
The plane raided was a regular passenger flight from Brussels to Zurich, operated by Helvetica Airlines, Van der Cruysse said.
The spokesman for the Antwerp World Diamond Centre said it was aware of reports that gold and platinum were stolen along with the diamonds, but he said he could not confirm that information.
On average, the Antwerp World Diamond Centre has $200 million in stones coming in and out daily, and it takes security very seriously, he added.
