Cash was stolen from a Pinner bookies after a man threatened staff with a handgun.
Officers from the Met's Flying Squad are investigating after police were called at 7.39pm on Thursday (November 23) to the Coral shop in Uxbridge Road, Hatch End , to reports of an armed robbery.
Passerby Jon Evans, who saw police at the the Coral bookies, said: "I didn’t see it but there were two police cars in attendance afterwards.
"The officer on duty wouldn’t give me details. The shop was cordoned off."
A Metropolitan Police spokesman said: "The suspect threatened staff with a handgun and made off with a small amount of cash.
"It is believed that a second suspect was standing outside the premises during the robbery.
"The first suspect is described as a male of Asian appearance, aged around 40, around 6ft 2in tall and of large build.
"He was wearing black gloves and dark coloured jeans.
"The second suspect is described as a white male, in his early/mid-20s and around 5ft 8in tall.
"He was of slim build and wearing a grey crash helmet."
Both suspects had their faces partially covered during the incident, police said.
No arrests have yet been made and police are continuing their enquiries.
If you have any information about this incident, call the Flying Squad on 101 or Crimestoppers on 0800 555 111.
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