A gunman who terrified staff as he carried out the UK's biggest jewellery robbery has been jailed for 23 years.
Aman Kassaye planned and executed the heist at Graff Diamonds in Mayfair, central London, last summer.
Gems worth up to £40 million were stolen at gunpoint. They have never been recovered.
Petra Ehnar, who had been working at the New Bond Street store at the time, told Woolwich Crown Court how she was forced to empty display cabinets with a gun to her back.
She was also bundled outside afterwards and told she would be killed if she did not carry out their demands.
Kassaye, of no fixed address, used a professional make-up artist to disguise his appearance and a series of getaway cars to escape.
He has been jailed for 16 years for conspiracy to rob, a further five years of possessing a firearm and another two years for kidnap.
Three other men - Solomun Beyene, 25, of Marylebone, north-west London; Clinton Mogg, 43, of Bournemouth; and Thomas Thomas, 46, of Penrhyn Road, Kingston upon Thames - were each jailed for 16 years after also being convicted of conspiracy to rob.
