BRUSSELS — In a meticulously planned heist that took barely five minutes to execute, armed men disguised as police officers drove onto the tarmac at the international airport in Brussels on Monday night and stole diamonds worth around $50 million as they were being loaded onto a plane bound for Switzerland, officials said.
The stolen gems, a mix of rough and cut stones, had arrived at the airport by road from the Belgian port city of Antwerp, the world’s biggest diamond trading center, and were to be flown on a scheduled passenger flight to Zurich, an important transit point in the global diamond business.
A spokeswoman for the Brussels prosecutors’ office told a news conference at the airport, known as Zaventem, that eight ‘‘heavily armed and hooded’’ thieves had driven onto the tarmac in two black vehicles with flashing lights, local media reported.
“This was not a random robbery. It was well-prepared — these were professionals,’’ said the spokeswoman, Anja Bijens, adding that the robbers had worn police uniforms and carried submachine guns. No shots were fired and no one was hurt.
The theft delivers a blow to Antwerp’s role as a diamond center.
“The fact that this happened is a big problem for us. We have our number one position to defend. Security is obviously very important,’’ said Caroline De Wolf, a spokeswoman for the Antwerp World Diamond Centre.
Helvetic Airways, an independent Swiss airline that operated the plane targeted in the robbery, said security for valuable cargo is normally the responsibility of the airport and the security company hired to transport the shipment to the plane.
An airline spokesman in Zurich declined to comment further.