A man went into a luxury watch store disguised as an OAP, pulled a gun on the cashier, and made her hand over jewellery worth £2.6millon.
The crook appeared to be wearing a latex mask to make him look old.
A CCTV camera caught the shocking heist as it unfolded.
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The footage shows how the spectacled man walks into the store wearing a flat cap and using a cane.
He walks towards the till and pulls a handgun from his satchel.
He then produces an oversized plastic bag, which he orders the female cashier to fill with pricey timepieces.
The pair proceed to clear out the window displays, even as passersby stop to gawp at the high-end pieces.
The heist took place at the Monaco Watch Company in Monaco on Wednesday (29 May) morning, as reported on Need To Know.
According to prosecutors, the smartly-dressed crook made off with jewellery worth more than £2.6million (€3million)
He is believed to have fled towards Beausoleil, France, on the pillion of a getaway scooter.
No shots were fired during the heist and the salesperson was uninjured.
However, she was taken to hospital after the ordeal in a state of shock.
The search for the two suspects continues.
A spokesperson for the Monaco Watch Company said: “As many of you already know a couple of days ago our beloved shop has been robbed.
“A masked man threatened our employee with a gun and forced her to empty the windows.
“Thankfully no one was physically injured during this process but the shock is very deep.”
They added: “This brutal setback is hitting us all in the hardest way possible but we won’t let ourselves down especially because all of you are giving us a huge amount of strength to go through this had period of time.
“With this video we wanted to thank you all for your support and even more the members that have the desire to leave them watches on consignment to us in order to reopen the shop as fast as possible with the maximum strength possible.
“Many thanks again to all of you from the bottom of our hearts for being so close to us.”
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