Police are appealing for the assistance of the public in finding a Taser electric shock weapon which has fallen from a Metropolitan Police vehicle in North Lambeth.
An officer from the Met's CO19 firearms unit attended a briefing at the service's Lambeth Road building between 7am and 8.30am on Tuesday.
The officer left the building and headed to a marked police vehicle parked in Norfolk Row (a small side-street off Old Paradise Street) where he placed the Taser on the roof as he prepared the car for use.
He then drove away from the base with the Taser still on the roof.
At around 10am officers noticed that the Taser was missing. Despite extensive searches they have been unable to find the Taser and four cartridges which were with it.
Officers believe the Taser would have fallen from the vehicle in the Norfolk Row area and almost certainly before reaching Vauxhall Cross where the vehicle stopped for fuel.
Officers are appealing for anyone with information as to the Taser's whereabouts to call the Metropolitan Police on 0300 123 1212.
The Taser broadly resembles a handgun in shape but is made of bright yellow plastic.
"We would ask anyone in possession of the Taser not to handle it, but to call police immediately," says a police spokesman.
"An internal investigation is underway. The Directorate of Professional Standards has been informed. The officer has been removed from operational firearms duty."