Terrified staff in a London Marks and Spencer's were herded by masked robbers into the store's food hall where they were bound with cable ties as suspects stole cash.
Detectives are now releasing CCTV footage of the commercial robbery in an attempt to identify the two suspects, one of whom was armed with a knife.
Just before 6.30am on November 27, two masked suspects entered the store in Mill Hill and herded staff into an area of the food hall, Metropolitan Police said.
One suspect, armed with a knife, tied up staff using cable ties as the second took a staff member to a till, where she was forced to open it.
After removing cash from the till the suspects left the store using the rear doors and walked along The Broadway towards Hale Lane and Bunns Lane.
They stole £200 from Marks and Spencer's, a police spokesman said.
After releasing CCTV footage of the staff's terrifying ordeal, detective constable Dan Levy of Barnet CID said: “This was a frightening experience for store staff at the scene.
“The suspects put the victims in a brief, but highly-threatening situation in order to steal £200.
“It is very important that we identify and apprehend these suspects as quickly as possible and I urge anyone who knows them or has information to come forward.”
Anyone with information should call Barnet CID by dialling 101, tweet @MetCC, or call Crimestoppers anonymously on 0800 555 111.
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