CCTV footage of robbers dressed as police forensics officers stealing diamond jewellery from a Lincoln shop has been released by police.
The footage shows one of the masked men threaten a staff member with a hammer at James Usher & Son in Guildhall Street in the raid on Saturday morning.
Managing director James Frampton said about £80,000 of jewels were stolen and security is now being reviewed.
The robbers escaped in a car later found abandoned and on fire.
The green Vauxhall Astra was set alight in Lindum Terrace.
‘Dangerous individuals’
The robbers and getaway driver then made their escape in a white Transit-type van parked on Arboretum Avenue, police said.
Officers said the two robbers – wearing white hooded-boiler suits with a "police forensics" logo and dust masks which covered most of their faces – took various pieces of diamond jewellery.
They appeared to target the most valuable items in the shop.
Mr Frampton said: "We are relieved that our staff are physically unharmed although some are struggling to come to terms with the shock of these events.
"We appeal to all members of the public who were in the vicinity and saw anything at all to help the police with their inquiries. It is important for us all that these dangerous individuals are apprehended."
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