A parcel of 120,000 carats of rough and polished diamonds worth $28 million was stolen from an ABN Amro Holding NV bank vault in Antwerp on March 5th, according to a statement from the Antwerp prosecutor's office, reports Bloomberg.

The main suspect was believed to be a regular client of the bank branch. He used the false identity Carlos Hector Flomenbaum in his bank dealings and was described as a tall man between 55 and 60 years-old, who spoke English with an American accent. Although he claimed he was Argentinean, his passport was found to be stolen in Israel a few years ago, according to reports.

The police, who are investigating the possibility of inside help, said that a reward of $2.64 million has been offered for information leading to the prosecution of the suspect.

�The stolen diamonds were owned by eight Antwerp-based diamond trading companies and given as a pledge to bank loans,� Philip Claes, a spokesman of the Antwerp World Diamond Center, told Bloomberg.

The stolen parcel contained a 133 carat rough diamond, which according to Claes, would be difficult to sell in the market, as all global diamond trading centres would be notified of the details. It also included 41 blue coloured brilliants and two natural green, pear-shaped stones, he added.