An investigation is under way after a policewoman left a loaded pistol in a Starbucks toilet.

The pistol was reportedly found on the toilet floor of a branch of the coffee shop in central London by a member of the public.

The highly-trained officer involved is believed to be part of former prime minister Tony Blair's protection team.

A Scotland Yard spokesman said: "A police-issue firearm was left unattended in a central London cafe on August 29 and was found by a member of the public.

"The weapon belongs to a Metropolitan Police authorised firearms officer who was on duty at the time."

A spokeswoman later confirmed that the abandoned gun had been loaded.

An investigation is being carried out by Scotland Yard's Directorate of Professional Standards.

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