The four robbers who stole £40 million worth of jewels from Mayfair's Graff Diamonds last summer have been sentenced to a total of 71 years in prison, The Daily Star reports.



The ringleader of the biggest jewel heist in UK history, Aman Kassaye, and his accomplices – Solomun Beyene, Clinton Mogg, and Thomas Thomas – held the staff of diamond supplier Graff Diamonds at gunpoint while forcing employee Petra Ehnar to empty the display cases.



Kassaye then forced Ehnar out of the store and onto the street at gunpoint, eventually making his getaway in a series of cars.



Forty-three pieces of jewelry – including one diamond necklace valued at £3.5 million – were taken during the robbery of the diamond company. The jewels have yet to be found or returned.



Although Kassaye had hired a professional makeup artist to disguise his appearance, Ehnar identified him. Kassaye, for his part, argued that someone else – bearing a striking resemblance to him – had been responsible for the robbery.



Kassaye was sentenced to 23 years in prison – 16 for conspiracy to rob, five years for being in possession of a firearm, and two years for kidnap. Each of the other three men was sentenced to 16 years on the charge of conspiracy to rob.