The victim, a man aged in his 40s, was approached by a man on a moped in the car park of Barclays, in High Road.
He then brandished a large blade at the victim and demanded his watch, which was worth a four-figure sum.
Fortunately, the victim was not hurt but is reportedly shaken by the experience.
It happened at around 6.10pm yesterday. Officers carried out a thorough search of the area but were unable to locate the moped, which has been described as black.
The rider wore a black top with jeans and a black helmet. He was described as being around 6ft tall.
Anyone who may have been in the High Road area at the time and seen a moped matching a similar description, or who has CCTV footage or dash cam footage available to view, is asked to call Essex Police on 101. The crime reference number to quote is 42/183113/18.
You can also contact Crimestoppers 100% anonymously on 0800 555 111.
Tags: Loughton, Epping Forest
