The Metropolitian Police's Flying Squad were called to the scene of a robbery at a supermarket.
Officers were called to the Rayners Lane branch of Sainsbury’s supermarket on Monday January 27 just before 7.20am after thieves stole cash.
Officers from Harrow and the Flying Squad attended the scene outside the supermarket.
No arrests have been made and police say enquiries are ongoing.
Officers have described the suspect as a black, of stocky build and wearing a high visibility jacket.
Anyone with any information about the incident are being called to contact police.