THE HAGUE: A Dutch court on Monday jailed three men over a daring $72 million (Dh264 billion) diamond robbery in 2005 at Amsterdam's Schiphol airport, one of the world's biggest ever heists, the court service said.

The armed robbers, disguised as KLM airline workers, stole diamonds and jewellery from a flight headed to the Belgian port of Antwerp and escaped in a stolen KLM van.

Seven suspects were eventually arrested in January 2017 in Amsterdam and Valencia in Spain after a years-long undercover investigation, with the help of a lucky break involving a radio intercept.

The two men in the getaway van, named as driver and ringleader Errol H.V., 54, and passenger Marlon D, 44, were sentenced to seven and six years respectively by the court in the central city of Haarlem.

A KLM employee named as Ramazan N, who gave the robbers KLM uniforms and helped smuggle weapons into the area, was jailed for five years, NOS television said.

"The armed robbery made a deep impression on the victims. They were threatened close up verbally and with weapons," the court service said in a statement, adding that it also caused "much social unrest".

Casualty

A fourth suspect involved in an earlier attempted robbery with the Schiphol driver was jailed for three and a half years.

Two other suspects were acquitted while the seventh suspect, and alleged brains of the operation, died recently.

Two women in relationships with two of the suspects were each jailed for three months for money laundering.

The audacious raid saw the robbers sneak into Schiphol's high-security area to target gems that were on their way to Antwerp, known as the world's diamond capital.

While some of the stolen diamonds were found in an escape vehicle immediately after the heist, the rest - valued at $43 million - remain unaccounted for.

The suspects were caught when a vigilant police officer involved in a separate investigation overheard the heist being discussed during an intercepted telephone conversation.

Police also discovered another link when one of the suspects allegedly admitted his involvement in the February 2005 robbery to undercover police.