It was all over in three minutes. That was all the time it took eight highly professional thieves disguised as policemen to remove diamonds weighing 22lbs, worth about $50m (€37m), from a plane in Belgium and speed away.
The gang, armed with machine guns, broke into Zaventem airport, Brussels, and raced up to the Swiss aircraft about to be cleared for take-off.
No shots were fired and no one was injured in the heist.
The first that the 22 passengers knew of the robbery was when their flight was cancelled a few moments later.
Last night, Antwerp – the world's oldest and biggest diamond-trading centre – was in shock at the ease with which one of the biggest diamond robberies in history was carried out on Monday evening.
Caroline de Wolf, spokesperson for the Antwerp World Diamond Centre, said: "Antwerp is the most highly secured diamond centre in the industry.
"We find it hard to understand how a robbery such as yesterday's could take place."
To minimise exposure to theft it is usual to move diamonds by air, and to load them into the hold of aircraft as late as possible before take-off. But these precautions were to no avail on Monday.
It was 7.47pm local time when the gang broke through the airport's security fence at a point between two construction sites.
A Mercedes van and an Audi saloon car, both with flashing blue lights, raced up to the plane, operated by Helvetica Airways, where a Brinks security van was in the process of loading the diamonds, both cut and uncut, into the aircraft's hold.
Four men wearing masks and hooded police cagoules leapt out of each vehicle and held the pilot, crew and other personnel at gunpoint while they removed the precious load.
Within three minutes the gang were back in their vehicles and heading for the hole in the fence. The Mercedes van was later found burnt out.
A manhunt was under way to trace the robbers and the other vehicle last night.
Today 80pc of rough diamonds and half of polished ones are traded in the city.
Karen Rentmeesters, an expert from the Antwerp World Diamond Centre, said: "It is virtually impossible to trace the stolen diamonds, whether rough or polished." Monday's exploit compares with the theft of diamonds worth €21m from an Antwerp bank in 2007 by a man with a false Argentinian passport who had charmed bank staff with gifts of chocolates.
And 10 years ago, three Italians and a Dutch woman succeeded in emptying 123 Antwerp bank safes of gold, diamonds and cash worth $180m (€135m).
However, that gang made an elementary error. On the motorway between Antwerp and Brussels, they dumped a bin bag containing CCTV footage of the heist, security passes, and documents that named one of the gang members, which led to the gang's swift capture. (© Independent News Service)