One of Tony Blair’s former protection officers has been suspended from her job after she accidentally left a loaded Glock 17 semi-automatic pistol in the toilet of a Starbucks coffee shop in Central London.

The authorised firearms officer, believed to be a member of the SO1 special protection unit, visited the toilet in a branch of Starbucks on Edgware Road last Friday. She re-emerged and continued her shift unaware that she had left the deadly weapon in the bathroom.

The gun was discovered by a member of the public who immediately dialled 999, Scotland Yard admitted today after a report in the Sun newspaper. The officer involved did not alert her superiors, a spokeswoman said, and the gun was not identified as hers until its serial number was compared to those logged at a police armoury.

The female officer, who has not been identified, is now being investigated by the Directorate of Professional Standards, Scotland Yard’s internal disciplinary body.

A police spokesman said today: “We do not know how long the investigation will last. It must be clear whether the person was negligent or not – because their career is on the line.”

The officer involved, who was once Tony Blair’s close protection officer, is thought to be a high-flying female officer in her 30s.

Scotland Yard said today that the gun had not been fired. “A police-issue firearm was left unattended in a central London cafe on August 29 and was found by a member of the public,” a spokesman said.

“The weapon belongs to a Metropolitan Police authorised firearms officer who was on duty at the time. The officer has been removed from operational duties while an investigation is carried out.”

The Metropolitan Police employs 2,586 authorised firearms officers.

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